Auto merge of #940 - fitzgen:no-syntex, r=emilio

No more syntex

There are a few commits in this PR, but the big one is the commit that goes `syntex` -> `quote` for code generation. I've included a copy of its commit message below.

I tried to verify that it works with the stylo build still, but there were some issues, and then I checked with master, and that wasn't working either. So now I'm C-Reducing the failures on master and figured that this is at least ready for feedback in the meantime.

r? @emilio

----------------------------

The `syntex` crate is unmaintained. It is slow to build, and additionally it requires that we pre-process `src/codegen/mod.rs` before we build the `bindgen` crate.

The `quote` crate provides similar quasi-quoting functionality, is maintained, and builds faster. It doesn't have a typed API or builders, however; it only deals with tokens.

Before this commit:

```
$ cargo clean; cargo build
<snip>
    Finished dev [unoptimized + debuginfo] target(s) in 98.75 secs
```

After this commit:

```
$ cargo clean; cargo build
<snip>
    Finished dev [unoptimized + debuginfo] target(s) in 46.26 secs
```

Build time is cut in half! But what about run time?

Before this commit:

```
Generated Stylo bindings in: Duration { secs: 3, nanos: 521105668 }
```

After this commit:

```
Generated Stylo bindings in: Duration { secs: 3, nanos: 548797242 }
```

So it appears to be about 20ms slower at generating Stylo bindings, but I suspect this is well within the noise.

Finally, this also lets us remove that nasty `mem::transmute` inside `bindgen::ir::BindgenContext::gen` that was used for the old `syntex` context. Now `BindgenContext` doesn't have a lifetime parameter either. This should make it easier to revisit doing our analyses in parallel with `rayon`, since that context was one of the things that made it hard for `BindgenContext` to implement `Sync`.

Fixes #925

23 files changed, 1450 insertions, 1709 deletions

diff --git a/src/codegen/derive_debug.rs b/src/codegen/derive_debug.rs
index 82456797..7ef108da 100644
--- a/src/codegen/derive_debug.rs
+++ b/src/codegen/derive_debug.rs
@@ -3,21 +3,17 @@ use ir::context::BindgenContext;
 use ir::derive::CanTriviallyDeriveDebug;
 use ir::item::{HasTypeParamInArray, IsOpaque, Item, ItemCanonicalName};
 use ir::ty::{RUST_DERIVE_IN_ARRAY_LIMIT, TypeKind};
-use syntax::ast;
-use syntax::codemap::DUMMY_SP;
-use syntax::parse::token::Token;
-
-use syntax::tokenstream::TokenTree;
+use quote;
 
 pub fn gen_debug_impl(
     ctx: &BindgenContext,
     fields: &[Field],
     item: &Item,
     kind: CompKind,
-) -> Vec<ast::ImplItem> {
+) -> quote::Tokens {
     let struct_name = item.canonical_name(ctx);
     let mut format_string = format!("{} {{{{ ", struct_name);
-    let mut tokens: Vec<TokenTree> = Vec::new();
+    let mut tokens = vec![];
 
     if item.is_opaque(ctx, &()) {
         format_string.push_str("opaque");
@@ -33,14 +29,11 @@ pub fn gen_debug_impl(
                 });
 
 
-                for (i, (fstring, token)) in processed_fields.enumerate() {
+                for (i, (fstring, toks)) in processed_fields.enumerate() {
                     if i > 0 {
                         format_string.push_str(", ");
                     }
-                    if !token.is_empty() {
-                        tokens.push(TokenTree::Token(DUMMY_SP, Token::Comma));
-                        tokens.extend(token);
-                    }
+                    tokens.extend(toks);
                     format_string.push_str(&fstring);
                 }
             }
@@ -48,17 +41,12 @@ pub fn gen_debug_impl(
     }
 
     format_string.push_str(" }}");
+    tokens.insert(0, quote! { #format_string });
 
-    let impl_ = quote_item!(ctx.ext_cx(),
-                            impl X {
-                                fn fmt(&self, f: &mut ::std::fmt::Formatter) -> ::std::fmt::Result {
-                                    write!(f, $format_string $tokens)
-                                }
-                            });
-
-    match impl_.unwrap().node {
-        ast::ItemKind::Impl(_, _, _, _, _, ref items) => items.clone(),
-        _ => unreachable!(),
+    quote! {
+        fn fmt(&self, f: &mut ::std::fmt::Formatter) -> ::std::fmt::Result {
+            write!(f, #( #tokens ),*)
+        }
     }
 }
 
@@ -74,7 +62,7 @@ pub trait ImplDebug<'a> {
         &self,
         ctx: &BindgenContext,
         extra: Self::Extra,
-    ) -> Option<(String, Vec<TokenTree>)>;
+    ) -> Option<(String, Vec<quote::Tokens>)>;
 }
 
 impl<'a> ImplDebug<'a> for FieldData {
@@ -84,7 +72,7 @@ impl<'a> ImplDebug<'a> for FieldData {
         &self,
         ctx: &BindgenContext,
         _: Self::Extra,
-    ) -> Option<(String, Vec<TokenTree>)> {
+    ) -> Option<(String, Vec<quote::Tokens>)> {
         if let Some(name) = self.name() {
             ctx.resolve_item(self.ty()).impl_debug(ctx, name)
         } else {
@@ -100,17 +88,18 @@ impl<'a> ImplDebug<'a> for BitfieldUnit {
         &self,
         ctx: &BindgenContext,
         _: Self::Extra,
-    ) -> Option<(String, Vec<TokenTree>)> {
+    ) -> Option<(String, Vec<quote::Tokens>)> {
         let mut format_string = String::new();
-        let mut tokens = Vec::new();
+        let mut tokens = vec![];
         for (i, bu) in self.bitfields().iter().enumerate() {
             if i > 0 {
                 format_string.push_str(", ");
-                tokens.push(TokenTree::Token(DUMMY_SP, Token::Comma));
             }
             format_string.push_str(&format!("{} : {{:?}}", bu.name()));
             let name_ident = ctx.rust_ident_raw(bu.name());
-            tokens.extend(quote_tokens!(ctx.ext_cx(), self.$name_ident()));
+            tokens.push(quote! {
+                self.#name_ident ()
+            });
         }
 
         Some((format_string, tokens))
@@ -123,8 +112,8 @@ impl<'a> ImplDebug<'a> for Item {
     fn impl_debug(
         &self,
         ctx: &BindgenContext,
-        name: Self::Extra,
-    ) -> Option<(String, Vec<TokenTree>)> {
+        name: &str,
+    ) -> Option<(String, Vec<quote::Tokens>)> {
         let name_ident = ctx.rust_ident_raw(name);
 
         // We don't know if blacklisted items `impl Debug` or not, so we can't
@@ -141,13 +130,14 @@ impl<'a> ImplDebug<'a> for Item {
         };
 
         fn debug_print(
-            ctx: &BindgenContext,
             name: &str,
-            name_ident: ast::Ident,
-        ) -> Option<(String, Vec<TokenTree>)> {
+            name_ident: quote::Tokens,
+        ) -> Option<(String, Vec<quote::Tokens>)> {
             Some((
                 format!("{}: {{:?}}", name),
-                quote_tokens!(ctx.ext_cx(), self.$name_ident),
+                vec![quote! {
+                    self.#name_ident
+                }],
             ))
         }
 
@@ -166,13 +156,13 @@ impl<'a> ImplDebug<'a> for Item {
             TypeKind::ObjCInterface(..) |
             TypeKind::ObjCId |
             TypeKind::Comp(..) |
-            TypeKind::ObjCSel => debug_print(ctx, name, name_ident),
+            TypeKind::ObjCSel => debug_print(name, quote! { #name_ident }),
 
             TypeKind::TemplateInstantiation(ref inst) => {
                 if inst.is_opaque(ctx, self) {
                     Some((format!("{}: opaque", name), vec![]))
                 } else {
-                    debug_print(ctx, name, name_ident)
+                    debug_print(name, quote! { #name_ident })
                 }
             }
 
@@ -189,18 +179,18 @@ impl<'a> ImplDebug<'a> for Item {
                     )
                 } else if len < RUST_DERIVE_IN_ARRAY_LIMIT {
                     // The simple case
-                    debug_print(ctx, name, name_ident)
+                    debug_print(name, quote! { #name_ident })
                 } else {
                     // Let's implement our own print function
                     Some((
                         format!("{}: [{{}}]", name),
-                        quote_tokens!(
-                        ctx.ext_cx(),
-                        self.$name_ident
-                            .iter()
-                            .enumerate()
-                            .map(|(i, v)| format!("{}{:?}", if i > 0 { ", " } else { "" }, v))
-                            .collect::<String>()),
+                        vec![quote! {
+                            self.#name_ident
+                                .iter()
+                                .enumerate()
+                                .map(|(i, v)| format!("{}{:?}", if i > 0 { ", " } else { "" }, v))
+                                .collect::<String>()
+                        }],
                     ))
                 }
             }
@@ -217,9 +207,9 @@ impl<'a> ImplDebug<'a> for Item {
                 match *inner_type.kind() {
                     TypeKind::Function(ref sig)
                         if !sig.can_trivially_derive_debug() => {
-                        Some((format!("{}: FunctionPointer", name), vec![]))
+                            Some((format!("{}: FunctionPointer", name), vec![]))
                     }
-                    _ => debug_print(ctx, name, name_ident),
+                    _ => debug_print(name, quote! { #name_ident }),
                 }
             }
 
diff --git a/src/codegen/helpers.rs b/src/codegen/helpers.rs
index ed165aa9..5136d787 100644
--- a/src/codegen/helpers.rs
+++ b/src/codegen/helpers.rs
@@ -1,66 +1,59 @@
 //! Helpers for code generation that don't need macro expansion.
 
-use aster;
 use ir::layout::Layout;
-use syntax::ast;
-use syntax::ptr::P;
-
+use quote;
 
 pub mod attributes {
-    use aster;
-    use syntax::ast;
-
-    pub fn allow(which_ones: &[&str]) -> ast::Attribute {
-        aster::AstBuilder::new()
-            .attr()
-            .list("allow")
-            .words(which_ones)
-            .build()
-    }
+    use quote;
 
-    pub fn repr(which: &str) -> ast::Attribute {
-        aster::AstBuilder::new()
-            .attr()
-            .list("repr")
-            .words(&[which])
-            .build()
+    pub fn repr(which: &str) -> quote::Tokens {
+        let which = quote::Ident::new(which);
+        quote! {
+            #[repr( #which )]
+        }
     }
 
-    pub fn repr_list(which_ones: &[&str]) -> ast::Attribute {
-        aster::AstBuilder::new()
-            .attr()
-            .list("repr")
-            .words(which_ones)
-            .build()
+    pub fn repr_list(which_ones: &[&str]) -> quote::Tokens {
+        let which_ones = which_ones.iter().cloned().map(quote::Ident::new);
+        quote! {
+            #[repr( #( #which_ones ),* )]
+        }
     }
 
-    pub fn derives(which_ones: &[&str]) -> ast::Attribute {
-        aster::AstBuilder::new()
-            .attr()
-            .list("derive")
-            .words(which_ones)
-            .build()
+    pub fn derives(which_ones: &[&str]) -> quote::Tokens {
+        let which_ones = which_ones.iter().cloned().map(quote::Ident::new);
+        quote! {
+            #[derive( #( #which_ones ),* )]
+        }
     }
 
-    pub fn inline() -> ast::Attribute {
-        aster::AstBuilder::new().attr().word("inline")
+    pub fn inline() -> quote::Tokens {
+        quote! {
+            #[inline]
+        }
     }
 
-    pub fn doc(comment: String) -> ast::Attribute {
-        aster::AstBuilder::new().attr().doc(&*comment)
+    pub fn doc(comment: String) -> quote::Tokens {
+        // Doc comments are already preprocessed into nice `///` formats by the
+        // time they get here. Just make sure that we have newlines around it so
+        // that nothing else gets wrapped into the comment.
+        let mut tokens = quote! {};
+        tokens.append("\n");
+        tokens.append(comment);
+        tokens.append("\n");
+        tokens
     }
 
-    pub fn link_name(name: &str) -> ast::Attribute {
-        aster::AstBuilder::new()
-            .attr()
-            .name_value("link_name")
-            .str(name)
+    pub fn link_name(name: &str) -> quote::Tokens {
+        quote! {
+            #[link_name = #name]
+        }
     }
 }
 
 /// Generates a proper type for a field or type with a given `Layout`, that is,
 /// a type with the correct size and alignment restrictions.
-pub fn blob(layout: Layout) -> P<ast::Ty> {
+pub fn blob(layout: Layout) -> quote::Tokens {
     let opaque = layout.opaque();
 
     // FIXME(emilio, #412): We fall back to byte alignment, but there are
@@ -75,39 +68,46 @@ pub fn blob(layout: Layout) -> P<ast::Ty> {
         }
     };
 
+    let ty_name = quote::Ident::new(ty_name);
+
     let data_len = opaque.array_size().unwrap_or(layout.size);
 
-    let inner_ty = aster::AstBuilder::new().ty().path().id(ty_name).build();
     if data_len == 1 {
-        inner_ty
+        quote! {
+            #ty_name
+        }
     } else {
-        aster::ty::TyBuilder::new().array(data_len).build(inner_ty)
+        quote! {
+            [ #ty_name ; #data_len ]
+        }
     }
 }
 
 pub mod ast_ty {
-    use aster;
     use ir::context::BindgenContext;
     use ir::function::FunctionSig;
     use ir::ty::FloatKind;
-    use syntax::ast;
-    use syntax::ptr::P;
+    use quote;
 
-    pub fn raw_type(ctx: &BindgenContext, name: &str) -> P<ast::Ty> {
-        let ident = ctx.rust_ident_raw(&name);
+    pub fn raw_type(ctx: &BindgenContext, name: &str) -> quote::Tokens {
+        let ident = ctx.rust_ident_raw(name);
         match ctx.options().ctypes_prefix {
             Some(ref prefix) => {
-                let prefix = ctx.rust_ident_raw(prefix);
-                quote_ty!(ctx.ext_cx(), $prefix::$ident)
+                let prefix = ctx.rust_ident_raw(prefix.as_str());
+                quote! {
+                    #prefix::#ident
+                }
             }
-            None => quote_ty!(ctx.ext_cx(), ::std::os::raw::$ident),
+            None => quote! {
+                ::std::os::raw::#ident
+            },
         }
     }
 
     pub fn float_kind_rust_type(
         ctx: &BindgenContext,
         fk: FloatKind,
-    ) -> P<ast::Ty> {
+    ) -> quote::Tokens {
         // TODO: we probably should just take the type layout into
         // account?
         //
@@ -116,64 +116,50 @@ pub mod ast_ty {
         // FIXME: `c_longdouble` doesn't seem to be defined in some
         // systems, so we use `c_double` directly.
         match (fk, ctx.options().convert_floats) {
-            (FloatKind::Float, true) => aster::ty::TyBuilder::new().f32(),
+            (FloatKind::Float, true) => quote! { f32 },
             (FloatKind::Double, true) |
-            (FloatKind::LongDouble, true) => aster::ty::TyBuilder::new().f64(),
+            (FloatKind::LongDouble, true) => quote! { f64 },
             (FloatKind::Float, false) => raw_type(ctx, "c_float"),
             (FloatKind::Double, false) |
             (FloatKind::LongDouble, false) => raw_type(ctx, "c_double"),
-            (FloatKind::Float128, _) => {
-                aster::ty::TyBuilder::new().array(16).u8()
-            }
+            (FloatKind::Float128, _) => quote! { [u8; 16] },
         }
     }
 
-    pub fn int_expr(val: i64) -> P<ast::Expr> {
-        use std::i64;
-        let expr = aster::AstBuilder::new().expr();
-
-        // This is not representable as an i64 if it's negative, so we
-        // special-case it.
-        //
-        // Fix in aster incoming.
-        if val == i64::MIN {
-            expr.neg().uint(1u64 << 63)
-        } else {
-            expr.int(val)
-        }
+    pub fn int_expr(val: i64) -> quote::Tokens {
+        // Don't use quote! { #val } because that adds the type suffix.
+        let mut tokens = quote! {};
+        tokens.append(val.to_string());
+        tokens
     }
 
-    pub fn bool_expr(val: bool) -> P<ast::Expr> {
-        aster::AstBuilder::new().expr().bool(val)
+    pub fn uint_expr(val: u64) -> quote::Tokens {
+        // Don't use quote! { #val } because that adds the type suffix.
+        let mut tokens = quote! {};
+        tokens.append(val.to_string());
+        tokens
     }
 
-    pub fn byte_array_expr(bytes: &[u8]) -> P<ast::Expr> {
-        let mut vec = Vec::with_capacity(bytes.len() + 1);
-        for byte in bytes {
-            vec.push(int_expr(*byte as i64));
+    pub fn byte_array_expr(bytes: &[u8]) -> quote::Tokens {
+        let mut bytes: Vec<_> = bytes.iter().cloned().collect();
+        bytes.push(0);
+        quote! {
+            #bytes
         }
-        vec.push(int_expr(0));
-
-        let kind = ast::ExprKind::Array(vec);
-
-        aster::AstBuilder::new().expr().build_expr_kind(kind)
     }
 
-    pub fn cstr_expr(mut string: String) -> P<ast::Expr> {
+    pub fn cstr_expr(mut string: String) -> quote::Tokens {
         string.push('\0');
-        aster::AstBuilder::new().expr().build_lit(
-            aster::AstBuilder::new()
-                .lit()
-                .byte_str(string),
-        )
+        let b = quote::ByteStr(&string);
+        quote! {
+            #b
+        }
     }
 
     pub fn float_expr(
         ctx: &BindgenContext,
         f: f64,
-    ) -> Result<P<ast::Expr>, ()> {
-        use aster::symbol::ToSymbol;
-
+    ) -> Result<quote::Tokens, ()> {
         if f.is_finite() {
             let mut string = f.to_string();
 
@@ -182,21 +168,28 @@ pub mod ast_ty {
                 string.push('.');
             }
 
-            let kind =
-                ast::LitKind::FloatUnsuffixed(string.as_str().to_symbol());
-            return Ok(aster::AstBuilder::new().expr().lit().build_lit(kind));
+            let mut tokens = quote! {};
+            tokens.append(string);
+            return Ok(tokens);
         }
 
         let prefix = ctx.trait_prefix();
+
         if f.is_nan() {
-            return Ok(quote_expr!(ctx.ext_cx(), ::$prefix::f64::NAN));
+            return Ok(quote! {
+                ::#prefix::f64::NAN
+            });
         }
 
         if f.is_infinite() {
             return Ok(if f.is_sign_positive() {
-                quote_expr!(ctx.ext_cx(), ::$prefix::f64::INFINITY)
+                quote! {
+                    ::#prefix::f64::INFINITY
+                }
             } else {
-                quote_expr!(ctx.ext_cx(), ::$prefix::f64::NEG_INFINITY)
+                quote! {
+                    ::#prefix::f64::NEG_INFINITY
+                }
             });
         }
 
@@ -207,23 +200,24 @@ pub mod ast_ty {
     pub fn arguments_from_signature(
         signature: &FunctionSig,
         ctx: &BindgenContext,
-    ) -> Vec<P<ast::Expr>> {
-        // TODO: We need to keep in sync the argument names, so we should unify
-        // this with the other loop that decides them.
+    ) -> Vec<quote::Tokens> {
         let mut unnamed_arguments = 0;
         signature
             .argument_types()
             .iter()
             .map(|&(ref name, _ty)| {
-                let arg_name = match *name {
-                    Some(ref name) => ctx.rust_mangle(name).into_owned(),
+                match *name {
+                    Some(ref name) => {
+                        let name = ctx.rust_ident(name);
+                        quote! { #name }
+                    }
                     None => {
                         unnamed_arguments += 1;
-                        format!("arg{}", unnamed_arguments)
+                        let name = ctx.rust_ident(format!("arg{}", unnamed_arguments));
+                        quote! { #name }
                     }
-                };
-                aster::expr::ExprBuilder::new().id(arg_name)
+                }
             })
-            .collect::<Vec<_>>()
+            .collect()
     }
 }
diff --git a/src/codegen/mod.rs b/src/codegen/mod.rs
index 4697ba21..f13bd65a 100644
--- a/src/codegen/mod.rs
+++ b/src/codegen/mod.rs
@@ -6,9 +6,6 @@ pub mod struct_layout;
 use self::helpers::attributes;
 use self::struct_layout::StructLayoutTracker;
 
-use aster;
-use aster::struct_field::StructFieldBuilder;
-
 use ir::annotations::FieldAccessorKind;
 use ir::comment;
 use ir::comp::{Base, Bitfield, BitfieldUnit, CompInfo, CompKind, Field,
@@ -29,36 +26,33 @@ use ir::template::{AsTemplateParam, TemplateInstantiation, TemplateParameters};
 use ir::ty::{Type, TypeKind};
 use ir::var::Var;
 
+use quote;
+
 use std::borrow::Cow;
 use std::cell::Cell;
 use std::collections::{HashSet, VecDeque};
 use std::collections::hash_map::{Entry, HashMap};
 use std::fmt::Write;
+use std::iter;
 use std::mem;
 use std::ops;
-use syntax::abi;
-use syntax::ast;
-use syntax::codemap::{DUMMY_SP, Span, respan};
-use syntax::ptr::P;
 
 // Name of type defined in constified enum module
 pub static CONSTIFIED_ENUM_MODULE_REPR_NAME: &'static str = "Type";
 
-fn top_level_path(ctx: &BindgenContext, item: &Item) -> Vec<ast::Ident> {
-    let mut path = vec![ctx.rust_ident_raw("self")];
+fn top_level_path(ctx: &BindgenContext, item: &Item) -> Vec<quote::Tokens> {
+    let mut path = vec![quote! { self }];
 
     if ctx.options().enable_cxx_namespaces {
-        let super_ = ctx.rust_ident_raw("super");
-
         for _ in 0..item.codegen_depth(ctx) {
-            path.push(super_.clone());
+            path.push(quote! { super });
         }
     }
 
     path
 }
 
-fn root_import(ctx: &BindgenContext, module: &Item) -> P<ast::Item> {
+fn root_import(ctx: &BindgenContext, module: &Item) -> quote::Tokens {
     assert!(ctx.options().enable_cxx_namespaces, "Somebody messed it up");
     assert!(module.is_module());
 
@@ -66,20 +60,20 @@ fn root_import(ctx: &BindgenContext, module: &Item) -> P<ast::Item> {
 
     let root = ctx.root_module().canonical_name(ctx);
     let root_ident = ctx.rust_ident(&root);
-    path.push(root_ident);
+    path.push(quote! { #root_ident });
+
 
-    let use_root = aster::AstBuilder::new()
-        .item()
-        .use_()
-        .ids(path)
-        .build()
-        .build();
+    let mut tokens = quote! {};
+    tokens.append_separated(path, "::");
 
-    quote_item!(ctx.ext_cx(), #[allow(unused_imports)] $use_root).unwrap()
+    quote! {
+        #[allow(unused_imports)]
+        use #tokens ;
+    }
 }
 
 struct CodegenResult<'a> {
-    items: Vec<P<ast::Item>>,
+    items: Vec<quote::Tokens>,
 
     /// A monotonic counter used to add stable unique id's to stuff that doesn't
     /// need to be referenced by anything.
@@ -190,7 +184,7 @@ impl<'a> CodegenResult<'a> {
         self.vars_seen.insert(name.into());
     }
 
-    fn inner<F>(&mut self, cb: F) -> Vec<P<ast::Item>>
+    fn inner<F>(&mut self, cb: F) -> Vec<quote::Tokens>
     where
         F: FnOnce(&mut Self),
     {
@@ -207,7 +201,7 @@ impl<'a> CodegenResult<'a> {
 }
 
 impl<'a> ops::Deref for CodegenResult<'a> {
-    type Target = Vec<P<ast::Item>>;
+    type Target = Vec<quote::Tokens>;
 
     fn deref(&self) -> &Self::Target {
         &self.items
@@ -220,70 +214,85 @@ impl<'a> ops::DerefMut for CodegenResult<'a> {
     }
 }
 
-struct ForeignModBuilder {
-    inner: ast::ForeignMod,
+/// A trait to convert a rust type into a pointer, optionally const, to the same
+/// type.
+trait ToPtr {
+    fn to_ptr(self, is_const: bool) -> quote::Tokens;
 }
 
-impl ForeignModBuilder {
-    fn new(abi: abi::Abi) -> Self {
-        ForeignModBuilder {
-            inner: ast::ForeignMod {
-                abi: abi,
-                items: vec![],
-            },
+impl ToPtr for quote::Tokens {
+    fn to_ptr(self, is_const: bool) -> quote::Tokens {
+        if is_const {
+            quote! { *const #self }
+        } else {
+            quote! { *mut #self }
         }
     }
-
-    fn with_foreign_item(mut self, item: ast::ForeignItem) -> Self {
-        self.inner.items.push(item);
-        self
-    }
-
-    #[allow(dead_code)]
-    fn with_foreign_items<I>(mut self, items: I) -> Self
-    where
-        I: IntoIterator<Item = ast::ForeignItem>,
-    {
-        self.inner.items.extend(items.into_iter());
-        self
-    }
-
-    fn build(self, ctx: &BindgenContext) -> P<ast::Item> {
-        P(ast::Item {
-            ident: ctx.rust_ident(""),
-            id: ast::DUMMY_NODE_ID,
-            node: ast::ItemKind::ForeignMod(self.inner),
-            vis: ast::Visibility::Public,
-            attrs: vec![],
-            span: DUMMY_SP,
-        })
-    }
 }
 
-/// A trait to convert a rust type into a pointer, optionally const, to the same
-/// type.
-///
-/// This is done due to aster's lack of pointer builder, I guess I should PR
-/// there.
-trait ToPtr {
-    fn to_ptr(self, is_const: bool, span: Span) -> P<ast::Ty>;
+/// An extension trait for `quote::Tokens` that lets us append any implicit
+/// template parameters that exist for some type, if necessary.
+trait AppendImplicitTemplateParams {
+    fn append_implicit_template_params(
+        &mut self,
+        ctx: &BindgenContext,
+        item: &Item,
+    );
 }
 
-impl ToPtr for P<ast::Ty> {
-    fn to_ptr(self, is_const: bool, span: Span) -> Self {
-        let ty = ast::TyKind::Ptr(ast::MutTy {
-            ty: self,
-            mutbl: if is_const {
-                ast::Mutability::Immutable
-            } else {
-                ast::Mutability::Mutable
-            },
-        });
-        P(ast::Ty {
-            id: ast::DUMMY_NODE_ID,
-            node: ty,
-            span: span,
-        })
+impl AppendImplicitTemplateParams for quote::Tokens {
+    fn append_implicit_template_params(
+        &mut self,
+        ctx: &BindgenContext,
+        item: &Item,
+    ) {
+        let item = item.id()
+            .into_resolver()
+            .through_type_refs()
+            .resolve(ctx);
+
+        match *item.expect_type().kind() {
+            TypeKind::UnresolvedTypeRef(..) => {
+                unreachable!("already resolved unresolved type refs")
+            }
+            TypeKind::ResolvedTypeRef(..) => {
+                unreachable!("we resolved item through type refs")
+            }
+
+            // None of these types ever have implicit template parameters.
+            TypeKind::Void |
+            TypeKind::NullPtr |
+            TypeKind::Pointer(..) |
+            TypeKind::Int(..) |
+            TypeKind::Float(..) |
+            TypeKind::Complex(..) |
+            TypeKind::Array(..) |
+            TypeKind::TypeParam |
+            TypeKind::Opaque |
+            TypeKind::Function(..) |
+            TypeKind::Enum(..) |
+            TypeKind::BlockPointer |
+            TypeKind::ObjCId |
+            TypeKind::ObjCSel |
+            TypeKind::TemplateInstantiation(..) => return,
+
+            _ => {},
+        }
+
+        if let Some(params) = item.used_template_params(ctx) {
+            if params.is_empty() {
+                return;
+            }
+
+            let params = params.into_iter().map(|p| {
+                p.try_to_rust_ty(ctx, &())
+                    .expect("template params cannot fail to be a rust type")
+            });
+
+            self.append(quote! {
+                < #( #params ),* >
+            });
+        }
     }
 }
 
@@ -376,7 +385,7 @@ impl CodeGenerator for Module {
                     utils::prepend_incomplete_array_types(ctx, &mut *result);
                 }
                 if ctx.need_bindegen_complex_type() {
-                    utils::prepend_complex_type(ctx, &mut *result);
+                    utils::prepend_complex_type(&mut *result);
                 }
                 if result.saw_objc {
                     utils::prepend_objc_header(ctx, &mut *result);
@@ -403,27 +412,23 @@ impl CodeGenerator for Module {
             return;
         }
 
-        let module = ast::ItemKind::Mod(ast::Mod {
-            inner: ctx.span(),
-            items: inner_items,
-        });
-
         let name = item.canonical_name(ctx);
-        let item_builder = aster::AstBuilder::new().item().pub_();
-        let item = if name == "root" {
-            let attrs = &[
-                "non_snake_case",
-                "non_camel_case_types",
-                "non_upper_case_globals",
-            ];
-            item_builder
-                .with_attr(attributes::allow(attrs))
-                .build_item_kind(name, module)
-        } else {
-            item_builder.build_item_kind(name, module)
-        };
 
-        result.push(item);
+        result.push(if name == "root" {
+            quote! {
+                #[allow(non_snake_case, non_camel_case_types, non_upper_case_globals)]
+                pub mod root {
+                    #( #inner_items )*
+                }
+            }
+        } else {
+            let ident = ctx.rust_ident(name);
+            quote! {
+                pub mod #ident {
+                    #( #inner_items )*
+                }
+            }
+        });
     }
 }
 
@@ -446,6 +451,8 @@ impl CodeGenerator for Var {
         }
         result.saw_var(&canonical_name);
 
+        let canonical_ident = ctx.rust_ident(&canonical_name);
+
         // We can't generate bindings to static variables of templates. The
         // number of actual variables for a single declaration are open ended
         // and we don't know what instantiations do or don't exist.
@@ -459,17 +466,17 @@ impl CodeGenerator for Var {
         let ty = self.ty().to_rust_ty_or_opaque(ctx, &());
 
         if let Some(val) = self.val() {
-            let const_item = aster::AstBuilder::new()
-                .item()
-                .pub_()
-                .const_(canonical_name)
-                .expr();
-            let item = match *val {
+            match *val {
                 VarType::Bool(val) => {
-                    const_item.build(helpers::ast_ty::bool_expr(val)).build(ty)
+                    result.push(quote! {
+                        pub const #canonical_ident : #ty = #val ;
+                    });
                 }
                 VarType::Int(val) => {
-                    const_item.build(helpers::ast_ty::int_expr(val)).build(ty)
+                    let val = helpers::ast_ty::int_expr(val);
+                    result.push(quote! {
+                        pub const #canonical_ident : #ty = #val ;
+                    });
                 }
                 VarType::String(ref bytes) => {
                     // Account the trailing zero.
@@ -477,35 +484,39 @@ impl CodeGenerator for Var {
                     // TODO: Here we ignore the type we just made up, probably
                     // we should refactor how the variable type and ty id work.
                     let len = bytes.len() + 1;
-                    let ty = quote_ty!(ctx.ext_cx(), [u8; $len]);
+                    let ty = quote! {
+                        [u8; #len]
+                    };
 
                     match String::from_utf8(bytes.clone()) {
                         Ok(string) => {
-                            const_item
-                                .build(helpers::ast_ty::cstr_expr(string))
-                                .build(quote_ty!(ctx.ext_cx(), &'static $ty))
+                            let cstr = helpers::ast_ty::cstr_expr(string);
+                            result.push(quote! {
+                                pub const #canonical_ident : &'static #ty = #cstr ;
+                            });
                         }
                         Err(..) => {
-                            const_item
-                                .build(helpers::ast_ty::byte_array_expr(bytes))
-                                .build(ty)
+                            let bytes = helpers::ast_ty::byte_array_expr(bytes);
+                            result.push(quote! {
+                                pub const #canonical_ident : #ty = #bytes ;
+                            });
                         }
                     }
                 }
                 VarType::Float(f) => {
                     match helpers::ast_ty::float_expr(ctx, f) {
-                        Ok(expr) => const_item.build(expr).build(ty),
+                        Ok(expr) => result.push(quote! {
+                            pub const #canonical_ident : #ty = #expr ;
+                        }),
                         Err(..) => return,
                     }
                 }
                 VarType::Char(c) => {
-                    const_item
-                        .build(aster::AstBuilder::new().expr().lit().byte(c))
-                        .build(ty)
+                    result.push(quote! {
+                        pub const #canonical_ident : #ty = #c ;
+                    });
                 }
-            };
-
-            result.push(item);
+            }
         } else {
             let mut attrs = vec![];
             if let Some(mangled) = self.mangled_name() {
@@ -514,19 +525,21 @@ impl CodeGenerator for Var {
                 attrs.push(attributes::link_name(self.name()));
             }
 
-            let item = ast::ForeignItem {
-                ident: ctx.rust_ident_raw(&canonical_name),
-                attrs: attrs,
-                node: ast::ForeignItemKind::Static(ty, !self.is_const()),
-                id: ast::DUMMY_NODE_ID,
-                span: ctx.span(),
-                vis: ast::Visibility::Public,
+            let mut tokens = quote! {
+                extern "C"
             };
+            tokens.append("{\n");
+            if !attrs.is_empty() {
+                tokens.append_separated(attrs, "\n");
+                tokens.append("\n");
+            }
+            tokens.append("pub static mut ");
+            tokens.append(quote! { #canonical_ident });
+            tokens.append(" : ");
+            tokens.append(quote! { #ty });
+            tokens.append(";\n}");
 
-            let item = ForeignModBuilder::new(abi::Abi::C)
-                .with_foreign_item(item)
-                .build(ctx);
-            result.push(item);
+            result.push(tokens);
         }
     }
 }
@@ -567,7 +580,9 @@ impl CodeGenerator for Type {
             TypeKind::Comp(ref ci) => ci.codegen(ctx, result, item),
             TypeKind::TemplateAlias(inner, _) |
             TypeKind::Alias(inner) => {
-                let inner_item = ctx.resolve_item(inner);
+                let inner_item = inner.into_resolver()
+                    .through_type_refs()
+                    .resolve(ctx);
                 let name = item.canonical_name(ctx);
 
                 // Try to catch the common pattern:
@@ -587,17 +602,25 @@ impl CodeGenerator for Type {
                     return;
                 }
 
-                let mut used_template_params = item.used_template_params(ctx);
+                let mut outer_params = item.used_template_params(ctx)
+                    .and_then(|ps| if ps.is_empty() {
+                        None
+                    } else {
+                        Some(ps)
+                    });
+
                 let inner_rust_type = if item.is_opaque(ctx, &()) {
-                    used_template_params = None;
+                    outer_params = None;
                     self.to_opaque(ctx, item)
                 } else {
                     // Its possible that we have better layout information than
                     // the inner type does, so fall back to an opaque blob based
                     // on our layout if converting the inner item fails.
-                    inner_item
+                    let mut inner_ty = inner_item
                         .try_to_rust_ty_or_opaque(ctx, &())
-                        .unwrap_or_else(|_| self.to_opaque(ctx, item))
+                        .unwrap_or_else(|_| self.to_opaque(ctx, item));
+                    inner_ty.append_implicit_template_params(ctx, inner_item);
+                    inner_ty
                 };
 
                 {
@@ -625,68 +648,71 @@ impl CodeGenerator for Type {
                 }
 
                 let rust_name = ctx.rust_ident(&name);
-                let mut typedef = aster::AstBuilder::new().item().pub_();
 
-                if let Some(comment) = item.comment(ctx) {
-                    typedef = typedef.with_attr(attributes::doc(comment));
-                }
+                let mut tokens = if let Some(comment) = item.comment(ctx) {
+                    attributes::doc(comment)
+                } else {
+                    quote! {}
+                };
 
                 // We prefer using `pub use` over `pub type` because of:
                 // https://github.com/rust-lang/rust/issues/26264
-                let simple_enum_path = match inner_rust_type.node {
-                    ast::TyKind::Path(None, ref p) => {
-                        if used_template_params.is_none() &&
-                            inner_item
-                                .expect_type()
-                                .canonical_type(ctx)
-                                .is_enum() &&
-                            p.segments.iter().all(|p| p.parameters.is_none())
-                        {
-                            Some(p.clone())
-                        } else {
-                            None
-                        }
-                    }
-                    _ => None,
-                };
+                if inner_rust_type.as_str()
+                    .chars()
+                    .all(|c| match c {
+                        // These are the only characters allowed in simple
+                        // paths, eg `good::dogs::Bront`.
+                        'A'...'Z' | 'a'...'z' | '0'...'9' | ':' | '_' | ' ' => true,
+                        _ => false,
+                    }) &&
+                    outer_params.is_none() &&
+                    inner_item.expect_type().canonical_type(ctx).is_enum()
+                {
+                    tokens.append(quote! {
+                        pub use
+                    });
+                    let path = top_level_path(ctx, item);
+                    tokens.append_separated(path, "::");
+                    tokens.append(quote! {
+                        :: #inner_rust_type  as #rust_name ;
+                    });
+                    result.push(tokens);
+                    return;
+                }
 
-                let typedef = if let Some(mut p) = simple_enum_path {
-                    for ident in top_level_path(ctx, item).into_iter().rev() {
-                        p.segments.insert(
-                            0,
-                            ast::PathSegment {
-                                identifier: ident,
-                                parameters: None,
-                            },
+                tokens.append(quote! {
+                    pub type #rust_name
+                });
+
+                if let Some(params) = outer_params {
+                    let params: Vec<_> = params.into_iter()
+                        .filter_map(|p| p.as_template_param(ctx, &()))
+                        .collect();
+                    if params.iter().any(|p| ctx.resolve_type(*p).is_invalid_type_param()) {
+                        warn!(
+                            "Item contained invalid template \
+                             parameter: {:?}",
+                            item
                         );
+                        return;
                     }
-                    typedef.use_().build(p).as_(rust_name)
-                } else {
-                    let mut generics = typedef.type_(rust_name).generics();
-                    if let Some(ref params) = used_template_params {
-                        for template_param in params {
-                            if let Some(id) = template_param
-                                .as_template_param(ctx, &())
-                            {
-                                let template_param = ctx.resolve_type(id);
-                                if template_param.is_invalid_type_param() {
-                                    warn!(
-                                        "Item contained invalid template \
-                                         parameter: {:?}",
-                                        item
-                                    );
-                                    return;
-                                }
-                                generics =
-                                    generics.ty_param_id(
-                                        template_param.name().unwrap(),
-                                    );
-                            }
-                        }
-                    }
-                    generics.build().build_ty(inner_rust_type)
-                };
-                result.push(typedef)
+
+                    let params = params.iter()
+                        .map(|p| {
+                            p.try_to_rust_ty(ctx, &())
+                                .expect("type parameters can always convert to rust ty OK")
+                        });
+
+                    tokens.append(quote! {
+                        < #( #params ),* >
+                    });
+                }
+
+                tokens.append(quote! {
+                    = #inner_rust_type ;
+                });
+
+                result.push(tokens);
             }
             TypeKind::Enum(ref ei) => ei.codegen(ctx, result, item),
             TypeKind::ObjCId | TypeKind::ObjCSel => {
@@ -738,17 +764,12 @@ impl<'a> CodeGenerator for Vtable<'a> {
 
         // For now, generate an empty struct, later we should generate function
         // pointers and whatnot.
-        let attributes = vec![attributes::repr("C")];
-
-        let vtable = aster::AstBuilder::new()
-            .item()
-            .pub_()
-            .with_attrs(attributes)
-            .tuple_struct(self.canonical_name(ctx))
-            .field()
-            .build_ty(helpers::ast_ty::raw_type(ctx, "c_void"))
-            .build();
-        result.push(vtable);
+        let name = ctx.rust_ident(&self.canonical_name(ctx));
+        let void = helpers::ast_ty::raw_type(ctx, "c_void");
+        result.push(quote! {
+            #[repr(C)]
+            pub struct #name ( #void );
+        });
     }
 }
 
@@ -765,8 +786,11 @@ impl<'a> TryToRustTy for Vtable<'a> {
         &self,
         ctx: &BindgenContext,
         _: &(),
-    ) -> error::Result<P<ast::Ty>> {
-        Ok(aster::ty::TyBuilder::new().id(self.canonical_name(ctx)))
+    ) -> error::Result<quote::Tokens> {
+        let name = ctx.rust_ident(self.canonical_name(ctx));
+        Ok(quote! {
+            #name
+        })
     }
 }
 
@@ -812,26 +836,28 @@ impl CodeGenerator for TemplateInstantiation {
                 write!(&mut fn_name, "_{}", times_seen).unwrap();
             }
 
-            let fn_name = ctx.rust_ident_raw(&fn_name);
+            let fn_name = ctx.rust_ident_raw(fn_name);
 
             let prefix = ctx.trait_prefix();
             let ident = item.to_rust_ty_or_opaque(ctx, &());
-            let size_of_expr = quote_expr!(ctx.ext_cx(),
-                                           ::$prefix::mem::size_of::<$ident>());
-            let align_of_expr = quote_expr!(ctx.ext_cx(),
-                                            ::$prefix::mem::align_of::<$ident>());
+            let size_of_expr = quote! {
+                ::#prefix::mem::size_of::<#ident>()
+            };
+            let align_of_expr = quote! {
+                ::#prefix::mem::align_of::<#ident>()
+            };
 
-            let item = quote_item!(
-                ctx.ext_cx(),
+            let item = quote! {
                 #[test]
-                fn $fn_name() {
-                    assert_eq!($size_of_expr, $size,
+                fn #fn_name() {
+                    assert_eq!(#size_of_expr, #size,
                                concat!("Size of template specialization: ",
-                                       stringify!($ident)));
-                    assert_eq!($align_of_expr, $align,
+                                       stringify!(#ident)));
+                    assert_eq!(#align_of_expr, #align,
                                concat!("Alignment of template specialization: ",
-                                       stringify!($ident)));
-                }).unwrap();
+                                       stringify!(#ident)));
+                }
+            };
 
             result.push(item);
         }
@@ -874,8 +900,8 @@ trait FieldCodegen<'a> {
         methods: &mut M,
         extra: Self::Extra,
     ) where
-        F: Extend<ast::StructField>,
-        M: Extend<ast::ImplItem>;
+        F: Extend<quote::Tokens>,
+        M: Extend<quote::Tokens>;
 }
 
 impl<'a> FieldCodegen<'a> for Field {
@@ -895,8 +921,8 @@ impl<'a> FieldCodegen<'a> for Field {
         methods: &mut M,
         _: (),
     ) where
-        F: Extend<ast::StructField>,
-        M: Extend<ast::ImplItem>,
+        F: Extend<quote::Tokens>,
+        M: Extend<quote::Tokens>,
     {
         match *self {
             Field::DataMember(ref data) => {
@@ -950,22 +976,27 @@ impl<'a> FieldCodegen<'a> for FieldData {
         methods: &mut M,
         _: (),
     ) where
-        F: Extend<ast::StructField>,
-        M: Extend<ast::ImplItem>,
+        F: Extend<quote::Tokens>,
+        M: Extend<quote::Tokens>,
     {
         // Bitfields are handled by `FieldCodegen` implementations for
         // `BitfieldUnit` and `Bitfield`.
         assert!(self.bitfield().is_none());
 
-        let field_ty = ctx.resolve_type(self.ty());
-        let ty = self.ty().to_rust_ty_or_opaque(ctx, &());
+        let field_item = self.ty().into_resolver().through_type_refs().resolve(ctx);
+        let field_ty = field_item.expect_type();
+        let mut ty = self.ty().to_rust_ty_or_opaque(ctx, &());
 
         // NB: If supported, we use proper `union` types.
         let ty = if parent.is_union() && !parent.can_be_rust_union(ctx) {
             if ctx.options().enable_cxx_namespaces {
-                quote_ty!(ctx.ext_cx(), root::__BindgenUnionField<$ty>)
+                quote! {
+                    root::__BindgenUnionField<#ty>
+                }
             } else {
-                quote_ty!(ctx.ext_cx(), __BindgenUnionField<$ty>)
+                quote! {
+                    __BindgenUnionField<#ty>
+                }
             }
         } else if let Some(item) = field_ty.is_incomplete_array(ctx) {
             result.saw_incomplete_array();
@@ -973,20 +1004,25 @@ impl<'a> FieldCodegen<'a> for FieldData {
             let inner = item.to_rust_ty_or_opaque(ctx, &());
 
             if ctx.options().enable_cxx_namespaces {
-                quote_ty!(ctx.ext_cx(), root::__IncompleteArrayField<$inner>)
+                quote! {
+                    root::__IncompleteArrayField<#inner>
+                }
             } else {
-                quote_ty!(ctx.ext_cx(), __IncompleteArrayField<$inner>)
+                quote! {
+                    __IncompleteArrayField<#inner>
+                }
             }
         } else {
+            ty.append_implicit_template_params(ctx, field_item);
             ty
         };
 
-        let mut attrs = vec![];
+        let mut field = quote! {};
         if ctx.options().generate_comments {
             if let Some(raw_comment) = self.comment() {
                 let comment =
                     comment::preprocess(raw_comment, codegen_depth + 1);
-                attrs.push(attributes::doc(comment))
+                field = attributes::doc(comment);
             }
         }
 
@@ -994,6 +1030,7 @@ impl<'a> FieldCodegen<'a> for FieldData {
             self.name()
                 .map(|name| ctx.rust_mangle(name).into_owned())
                 .unwrap_or_else(|| anon_field_names.next().unwrap());
+        let field_ident = ctx.rust_ident_raw(field_name.as_str());
 
         if !parent.is_union() {
             if let Some(padding_field) =
@@ -1010,14 +1047,16 @@ impl<'a> FieldCodegen<'a> for FieldData {
         let accessor_kind =
             self.annotations().accessor_kind().unwrap_or(accessor_kind);
 
-        let mut field = StructFieldBuilder::named(&field_name);
-
-        if !is_private {
-            field = field.pub_();
+        if is_private {
+            field.append(quote! {
+                #field_ident : #ty ,
+            });
+        } else {
+            field.append(quote! {
+                pub #field_ident : #ty ,
+            });
         }
 
-        let field = field.with_attrs(attrs).build_ty(ty.clone());
-
         fields.extend(Some(field));
 
         // TODO: Factor the following code out, please!
@@ -1025,98 +1064,58 @@ impl<'a> FieldCodegen<'a> for FieldData {
             return;
         }
 
-        let getter_name = ctx.rust_ident_raw(&format!("get_{}", field_name));
+        let getter_name = ctx.rust_ident_raw(format!("get_{}", field_name));
         let mutable_getter_name =
-            ctx.rust_ident_raw(&format!("get_{}_mut", field_name));
-        let field_name = ctx.rust_ident_raw(&field_name);
+            ctx.rust_ident_raw(format!("get_{}_mut", field_name));
+        let field_name = ctx.rust_ident_raw(field_name);
 
-        let accessor_methods_impl = match accessor_kind {
+        methods.extend(Some(match accessor_kind {
             FieldAccessorKind::None => unreachable!(),
             FieldAccessorKind::Regular => {
-                quote_item!(ctx.ext_cx(),
-                    impl X {
-                        #[inline]
-                        pub fn $getter_name(&self) -> &$ty {
-                            &self.$field_name
-                        }
+                quote! {
+                    #[inline]
+                    pub fn #getter_name(&self) -> & #ty {
+                        &self.#field_name
+                    }
 
-                        #[inline]
-                        pub fn $mutable_getter_name(&mut self) -> &mut $ty {
-                            &mut self.$field_name
-                        }
+                    #[inline]
+                    pub fn #mutable_getter_name(&mut self) -> &mut #ty {
+                        &mut self.#field_name
                     }
-                )
+                }
             }
             FieldAccessorKind::Unsafe => {
-                quote_item!(ctx.ext_cx(),
-                    impl X {
-                        #[inline]
-                        pub unsafe fn $getter_name(&self) -> &$ty {
-                            &self.$field_name
-                        }
+                quote! {
+                    #[inline]
+                    pub unsafe fn #getter_name(&self) -> & #ty {
+                        &self.#field_name
+                    }
 
-                        #[inline]
-                        pub unsafe fn $mutable_getter_name(&mut self)
-                            -> &mut $ty {
-                            &mut self.$field_name
-                        }
+                    #[inline]
+                    pub unsafe fn #mutable_getter_name(&mut self) -> &mut #ty {
+                        &mut self.#field_name
                     }
-                )
+                }
             }
             FieldAccessorKind::Immutable => {
-                quote_item!(ctx.ext_cx(),
-                    impl X {
-                        #[inline]
-                        pub fn $getter_name(&self) -> &$ty {
-                            &self.$field_name
-                        }
+                quote! {
+                    #[inline]
+                    pub fn #getter_name(&self) -> & #ty {
+                        &self.#field_name
                     }
-                )
-            }
-        };
-
-        match accessor_methods_impl.unwrap().node {
-            ast::ItemKind::Impl(_, _, _, _, _, ref items) => {
-                methods.extend(items.clone())
+                }
             }
-            _ => unreachable!(),
-        }
+        }));
     }
 }
 
 impl BitfieldUnit {
     /// Get the constructor name for this bitfield unit.
-    fn ctor_name(&self, ctx: &BindgenContext) -> ast::Ident {
-        let ctor_name = format!("new_bitfield_{}", self.nth());
-        ctx.ext_cx().ident_of(&ctor_name)
-    }
-
-    /// Get the initial bitfield unit constructor that just returns 0. This will
-    /// then be extended by each bitfield in the unit. See `extend_ctor_impl`
-    /// below.
-    fn initial_ctor_impl(
-        &self,
-        ctx: &BindgenContext,
-        unit_field_int_ty: &P<ast::Ty>,
-    ) -> P<ast::Item> {
-        let ctor_name = self.ctor_name(ctx);
-
-        // If supported, add the const.
-        let fn_prefix = if ctx.options().rust_features().const_fn() {
-            quote_tokens!(ctx.ext_cx(), pub const fn)
-        } else {
-            quote_tokens!(ctx.ext_cx(), pub fn)
-        };
-
-        quote_item!(
-            ctx.ext_cx(),
-            impl XxxUnused {
-                #[inline]
-                $fn_prefix $ctor_name() -> $unit_field_int_ty {
-                    0
-                }
-            }
-        ).unwrap()
+    fn ctor_name(&self) -> quote::Tokens {
+        let ctor_name = quote::Ident::new(format!("new_bitfield_{}", self.nth()));
+        quote! {
+            #ctor_name
+        }
     }
 }
 
@@ -1131,57 +1130,26 @@ impl Bitfield {
     fn extend_ctor_impl(
         &self,
         ctx: &BindgenContext,
-        parent: &CompInfo,
-        ctor_impl: P<ast::Item>,
-        ctor_name: &ast::Ident,
-        unit_field_int_ty: &P<ast::Ty>,
-    ) -> P<ast::Item> {
-        let items = match ctor_impl.unwrap().node {
-            ast::ItemKind::Impl(_, _, _, _, _, items) => items,
-            _ => unreachable!(),
-        };
-
-        assert_eq!(items.len(), 1);
-        let (sig, body) = match items[0].node {
-            ast::ImplItemKind::Method(ref sig, ref body) => (sig, body),
-            _ => unreachable!(),
-        };
-
-        let params = sig.decl.clone().unwrap().inputs;
-        let param_name = bitfield_getter_name(ctx, parent, self.name());
-
-        let bitfield_ty_item = ctx.resolve_item(self.ty());
-        let bitfield_ty = bitfield_ty_item.expect_type();
+        param_name: quote::Tokens,
+        ctor_impl: quote::Tokens,
+        unit_field_int_ty: &quote::Tokens,
+    ) -> quote::Tokens {
+        let bitfield_ty = ctx.resolve_type(self.ty());
         let bitfield_ty_layout = bitfield_ty.layout(ctx).expect(
             "Bitfield without layout? Gah!",
         );
         let bitfield_int_ty = helpers::blob(bitfield_ty_layout);
-        let bitfield_ty =
-            bitfield_ty.to_rust_ty_or_opaque(ctx, bitfield_ty_item);
 
         let offset = self.offset_into_unit();
         let mask = self.mask();
 
-        // If supported, add the const.
-        let fn_prefix = if ctx.options().rust_features().const_fn() {
-            quote_tokens!(ctx.ext_cx(), pub const fn)
-        } else {
-            quote_tokens!(ctx.ext_cx(), pub fn)
-        };
-
-        // Don't use variables or blocks because const function does not allow them.
-        quote_item!(
-            ctx.ext_cx(),
-            impl XxxUnused {
-                #[inline]
-                $fn_prefix $ctor_name($params $param_name : $bitfield_ty)
-                                      -> $unit_field_int_ty {
-                    ($body |
-                        (($param_name as $bitfield_int_ty as $unit_field_int_ty) << $offset) &
-                        ($mask as $unit_field_int_ty))
-                }
-            }
-        ).unwrap()
+        // Don't use variables or blocks because const functions do not allow
+        // them.
+        quote! {
+            (#ctor_impl |
+             ((#param_name as #bitfield_int_ty as #unit_field_int_ty) << #offset) &
+             (#mask as #unit_field_int_ty))
+        }
     }
 }
 
@@ -1202,15 +1170,16 @@ impl<'a> FieldCodegen<'a> for BitfieldUnit {
         methods: &mut M,
         _: (),
     ) where
-        F: Extend<ast::StructField>,
-        M: Extend<ast::ImplItem>,
+        F: Extend<quote::Tokens>,
+        M: Extend<quote::Tokens>,
     {
         let field_ty = helpers::blob(self.layout());
         let unit_field_name = format!("_bitfield_{}", self.nth());
+        let unit_field_ident = ctx.rust_ident(&unit_field_name);
 
-        let field = StructFieldBuilder::named(&unit_field_name)
-            .pub_()
-            .build_ty(field_ty.clone());
+        let field = quote! {
+            pub #unit_field_ident : #field_ty ,
+        };
         fields.extend(Some(field));
 
         let mut field_int_size = self.layout().size;
@@ -1219,10 +1188,10 @@ impl<'a> FieldCodegen<'a> for BitfieldUnit {
         }
 
         let unit_field_int_ty = match field_int_size {
-            8 => quote_ty!(ctx.ext_cx(), u64),
-            4 => quote_ty!(ctx.ext_cx(), u32),
-            2 => quote_ty!(ctx.ext_cx(), u16),
-            1 => quote_ty!(ctx.ext_cx(), u8),
+            8 => quote! { u64 },
+            4 => quote! { u32 },
+            2 => quote! { u16 },
+            1 => quote! { u8  },
             size => {
                 debug_assert!(size > 8);
                 // Can't generate bitfield accessors for unit sizes larget than
@@ -1232,8 +1201,9 @@ impl<'a> FieldCodegen<'a> for BitfieldUnit {
             }
         };
 
-        let ctor_name = self.ctor_name(ctx);
-        let mut ctor_impl = self.initial_ctor_impl(ctx, &unit_field_int_ty);
+        let ctor_name = self.ctor_name();
+        let mut ctor_params = vec![];
+        let mut ctor_impl = quote! { 0 };
 
         for bf in self.bitfields() {
             bf.codegen(
@@ -1250,23 +1220,36 @@ impl<'a> FieldCodegen<'a> for BitfieldUnit {
                 (&unit_field_name, unit_field_int_ty.clone()),
             );
 
+            let param_name = bitfield_getter_name(ctx, parent, bf.name());
+            let bitfield_ty_item = ctx.resolve_item(bf.ty());
+            let bitfield_ty = bitfield_ty_item.expect_type();
+            let bitfield_ty =
+                bitfield_ty.to_rust_ty_or_opaque(ctx, bitfield_ty_item);
+
+            ctor_params.push(quote! {
+                #param_name : #bitfield_ty
+            });
             ctor_impl = bf.extend_ctor_impl(
                 ctx,
-                parent,
+                param_name,
                 ctor_impl,
-                &ctor_name,
                 &unit_field_int_ty,
             );
         }
 
-        match ctor_impl.unwrap().node {
-            ast::ItemKind::Impl(_, _, _, _, _, items) => {
-                assert_eq!(items.len(), 1);
-                methods.extend(items.into_iter());
-            }
-            _ => unreachable!(),
+        let const_ = if ctx.options().rust_features().const_fn() {
+            quote! { const }
+        } else {
+            quote! { }
         };
 
+        methods.extend(Some(quote! {
+            #[inline]
+            pub #const_ fn #ctor_name ( #( #ctor_params ),* ) -> #unit_field_int_ty {
+                #ctor_impl
+            }
+        }));
+
         struct_layout.saw_bitfield_unit(self.layout());
     }
 }
@@ -1297,23 +1280,25 @@ fn bitfield_getter_name(
     ctx: &BindgenContext,
     parent: &CompInfo,
     bitfield_name: &str,
-) -> ast::Ident {
+) -> quote::Tokens {
     let name = ctx.rust_mangle(bitfield_name);
 
     if parent_has_method(ctx, parent, &name) {
         let mut name = name.to_string();
         name.push_str("_bindgen_bitfield");
-        return ctx.ext_cx().ident_of(&name);
+        let name = ctx.rust_ident(name);
+        return quote! { #name };
     }
 
-    ctx.ext_cx().ident_of(&name)
+    let name = ctx.rust_ident(name);
+    quote! { #name }
 }
 
 fn bitfield_setter_name(
     ctx: &BindgenContext,
     parent: &CompInfo,
     bitfield_name: &str,
-) -> ast::Ident {
+) -> quote::Tokens {
     let setter = format!("set_{}", bitfield_name);
     let mut setter = ctx.rust_mangle(&setter).to_string();
 
@@ -1321,11 +1306,12 @@ fn bitfield_setter_name(
         setter.push_str("_bindgen_bitfield");
     }
 
-    ctx.ext_cx().ident_of(&setter)
+    let setter = ctx.rust_ident(setter);
+    quote! { #setter }
 }
 
 impl<'a> FieldCodegen<'a> for Bitfield {
-    type Extra = (&'a str, P<ast::Ty>);
+    type Extra = (&'a str, quote::Tokens);
 
     fn codegen<F, M>(
         &self,
@@ -1339,15 +1325,15 @@ impl<'a> FieldCodegen<'a> for Bitfield {
         _struct_layout: &mut StructLayoutTracker,
         _fields: &mut F,
         methods: &mut M,
-        (unit_field_name, unit_field_int_ty): (&'a str, P<ast::Ty>),
+        (unit_field_name, unit_field_int_ty): (&'a str, quote::Tokens),
     ) where
-        F: Extend<ast::StructField>,
-        M: Extend<ast::ImplItem>,
+        F: Extend<quote::Tokens>,
+        M: Extend<quote::Tokens>,
     {
         let prefix = ctx.trait_prefix();
         let getter_name = bitfield_getter_name(ctx, parent, self.name());
         let setter_name = bitfield_setter_name(ctx, parent, self.name());
-        let unit_field_ident = ctx.ext_cx().ident_of(unit_field_name);
+        let unit_field_ident = quote::Ident::new(unit_field_name);
 
         let bitfield_ty_item = ctx.resolve_item(self.ty());
         let bitfield_ty = bitfield_ty_item.expect_type();
@@ -1363,67 +1349,57 @@ impl<'a> FieldCodegen<'a> for Bitfield {
         let offset = self.offset_into_unit();
         let mask = self.mask();
 
-        let impl_item = quote_item!(
-            ctx.ext_cx(),
-            impl XxxIgnored {
-                #[inline]
-                pub fn $getter_name(&self) -> $bitfield_ty {
-                    let mut unit_field_val: $unit_field_int_ty = unsafe {
-                        ::$prefix::mem::uninitialized()
-                    };
+        methods.extend(Some(quote! {
+            #[inline]
+            pub fn #getter_name(&self) -> #bitfield_ty {
+                let mut unit_field_val: #unit_field_int_ty = unsafe {
+                    ::#prefix::mem::uninitialized()
+                };
 
-                    unsafe {
-                        ::$prefix::ptr::copy_nonoverlapping(
-                            &self.$unit_field_ident as *const _ as *const u8,
-                            &mut unit_field_val as *mut $unit_field_int_ty as *mut u8,
-                            ::$prefix::mem::size_of::<$unit_field_int_ty>(),
-                        )
-                    };
+                unsafe {
+                    ::#prefix::ptr::copy_nonoverlapping(
+                        &self.#unit_field_ident as *const _ as *const u8,
+                        &mut unit_field_val as *mut #unit_field_int_ty as *mut u8,
+                        ::#prefix::mem::size_of::<#unit_field_int_ty>(),
+                    )
+                };
 
-                    let mask = $mask as $unit_field_int_ty;
-                    let val = (unit_field_val & mask) >> $offset;
-                    unsafe {
-                        ::$prefix::mem::transmute(val as $bitfield_int_ty)
-                    }
+                let mask = #mask as #unit_field_int_ty;
+                let val = (unit_field_val & mask) >> #offset;
+                unsafe {
+                    ::#prefix::mem::transmute(val as #bitfield_int_ty)
                 }
+            }
 
-                #[inline]
-                pub fn $setter_name(&mut self, val: $bitfield_ty) {
-                    let mask = $mask as $unit_field_int_ty;
-                    let val = val as $bitfield_int_ty as $unit_field_int_ty;
+            #[inline]
+            pub fn #setter_name(&mut self, val: #bitfield_ty) {
+                let mask = #mask as #unit_field_int_ty;
+                let val = val as #bitfield_int_ty as #unit_field_int_ty;
 
-                    let mut unit_field_val: $unit_field_int_ty = unsafe {
-                        ::$prefix::mem::uninitialized()
-                    };
+                let mut unit_field_val: #unit_field_int_ty = unsafe {
+                    ::#prefix::mem::uninitialized()
+                };
 
-                    unsafe {
-                        ::$prefix::ptr::copy_nonoverlapping(
-                            &self.$unit_field_ident as *const _ as *const u8,
-                            &mut unit_field_val as *mut $unit_field_int_ty as *mut u8,
-                            ::$prefix::mem::size_of::<$unit_field_int_ty>(),
-                        )
-                    };
+                unsafe {
+                    ::#prefix::ptr::copy_nonoverlapping(
+                        &self.#unit_field_ident as *const _ as *const u8,
+                        &mut unit_field_val as *mut #unit_field_int_ty as *mut u8,
+                        ::#prefix::mem::size_of::< #unit_field_int_ty >(),
+                    )
+                };
 
-                    unit_field_val &= !mask;
-                    unit_field_val |= (val << $offset) & mask;
+                unit_field_val &= !mask;
+                unit_field_val |= (val << #offset) & mask;
 
-                    unsafe {
-                        ::$prefix::ptr::copy_nonoverlapping(
-                            &unit_field_val as *const _ as *const u8,
-                            &mut self.$unit_field_ident as *mut _ as *mut u8,
-                            ::$prefix::mem::size_of::<$unit_field_int_ty>(),
-                        );
-                    }
+                unsafe {
+                    ::#prefix::ptr::copy_nonoverlapping(
+                        &unit_field_val as *const _ as *const u8,
+                        &mut self.#unit_field_ident as *mut _ as *mut u8,
+                        ::#prefix::mem::size_of::< #unit_field_int_ty >(),
+                    );
                 }
             }
-        ).unwrap();
-
-        match impl_item.unwrap().node {
-            ast::ItemKind::Impl(_, _, _, _, _, items) => {
-                methods.extend(items.into_iter());
-            }
-            _ => unreachable!(),
-        };
+        }));
     }
 }
 
@@ -1454,13 +1430,12 @@ impl CodeGenerator for CompInfo {
         // collisions.
         if self.is_forward_declaration() && used_template_params.is_none() {
             let struct_name = item.canonical_name(ctx);
-            let struct_name = ctx.rust_ident_raw(&struct_name);
-            let tuple_struct = quote_item!(ctx.ext_cx(),
-                                           #[repr(C)]
-                                           #[derive(Debug, Copy, Clone)]
-                                           pub struct $struct_name { _unused: [u8; 0] };
-                                          )
-                .unwrap();
+            let struct_name = ctx.rust_ident_raw(struct_name);
+            let tuple_struct = quote! {
+                #[repr(C)]
+                #[derive(Debug, Copy, Clone)]
+                pub struct #struct_name { _unused: [u8; 0] }
+            };
             result.push(tuple_struct);
             return;
         }
@@ -1527,18 +1502,17 @@ impl CodeGenerator for CompInfo {
         }
 
         let canonical_name = item.canonical_name(ctx);
-        let builder = if is_union && self.can_be_rust_union(ctx) {
-            aster::AstBuilder::new()
-                .item()
-                .pub_()
-                .with_attrs(attributes)
-                .union_(&canonical_name)
+        let canonical_ident = ctx.rust_ident(&canonical_name);
+        let mut tokens = if is_union && self.can_be_rust_union(ctx) {
+            quote! {
+                #( #attributes )*
+                pub union #canonical_ident
+            }
         } else {
-            aster::AstBuilder::new()
-                .item()
-                .pub_()
-                .with_attrs(attributes)
-                .struct_(&canonical_name)
+            quote! {
+                #( #attributes )*
+                pub struct #canonical_ident
+            }
         };
 
         // Generate the vtable from the method list if appropriate.
@@ -1567,15 +1541,13 @@ impl CodeGenerator for CompInfo {
                 let vtable_type = vtable
                     .try_to_rust_ty(ctx, &())
                     .expect("vtable to Rust type conversion is infallible")
-                    .to_ptr(true, ctx.span());
+                    .to_ptr(true);
 
-                let vtable_field = StructFieldBuilder::named("vtable_")
-                    .pub_()
-                    .build_ty(vtable_type);
+                fields.push(quote! {
+                    pub vtable_: #vtable_type ,
+                });
 
                 struct_layout.saw_vtable();
-
-                fields.push(vtable_field);
             }
 
             for (i, base) in self.base_members().iter().enumerate() {
@@ -1596,17 +1568,17 @@ impl CodeGenerator for CompInfo {
                 }
 
                 let inner = base.ty.to_rust_ty_or_opaque(ctx, &());
-                let field_name = if i == 0 {
+                let field_name = ctx.rust_ident(if i == 0 {
                     "_base".into()
                 } else {
                     format!("_base_{}", i)
-                };
+                });
 
                 struct_layout.saw_base(base_ty);
 
-                let field =
-                    StructFieldBuilder::named(field_name).pub_().build_ty(inner);
-                fields.extend(Some(field));
+                fields.push(quote! {
+                    pub #field_name : #inner ,
+                });
             }
         }
         if is_union {
@@ -1647,17 +1619,17 @@ impl CodeGenerator for CompInfo {
             let layout = layout.expect("Unable to get layout information?");
             let ty = helpers::blob(layout);
 
-            let field = if self.can_be_rust_union(ctx) {
-                StructFieldBuilder::named("_bindgen_union_align").build_ty(ty)
+            fields.push(if self.can_be_rust_union(ctx) {
+                quote! {
+                    _bindgen_union_align: #ty ,
+                }
             } else {
                 struct_layout.saw_union(layout);
 
-                StructFieldBuilder::named("bindgen_union_field")
-                    .pub_()
-                    .build_ty(ty)
-            };
-
-            fields.push(field);
+                quote! {
+                    pub bindgen_union_field: #ty ,
+                }
+            });
         }
 
         if is_opaque {
@@ -1668,11 +1640,9 @@ impl CodeGenerator for CompInfo {
             match layout {
                 Some(l) => {
                     let ty = helpers::blob(l);
-                    let field = StructFieldBuilder::named(
-                        "_bindgen_opaque_blob",
-                    ).pub_()
-                        .build_ty(ty);
-                    fields.push(field);
+                    fields.push(quote! {
+                        pub _bindgen_opaque_blob: #ty ,
+                    });
                 }
                 None => {
                     warn!("Opaque type without layout! Expect dragons!");
@@ -1713,41 +1683,45 @@ impl CodeGenerator for CompInfo {
 
             if has_address {
                 let ty = helpers::blob(Layout::new(1, 1));
-                let field =
-                    StructFieldBuilder::named("_address").pub_().build_ty(ty);
-                fields.push(field);
+                fields.push(quote! {
+                    pub _address: #ty,
+                });
             }
         }
 
-        let mut generics = aster::AstBuilder::new().generics();
+        let mut generics = quote! {};
 
         if let Some(ref params) = used_template_params {
-            for (idx, ty) in params.iter().enumerate() {
-                let param = ctx.resolve_type(*ty);
-                let name = param.name().unwrap();
-                let ident = ctx.rust_ident(name);
+            if !params.is_empty() {
+                let mut param_names = vec![];
 
-                generics = generics.ty_param_id(ident);
+                for (idx, ty) in params.iter().enumerate() {
+                    let param = ctx.resolve_type(*ty);
+                    let name = param.name().unwrap();
+                    let ident = ctx.rust_ident(name);
+                    param_names.push(ident.clone());
 
-                let prefix = ctx.trait_prefix();
-                let phantom_ty = quote_ty!(
-                    ctx.ext_cx(),
-                    ::$prefix::marker::PhantomData<::$prefix::cell::UnsafeCell<$ident>>);
-                let phantom_field = StructFieldBuilder::named(
-                    format!("_phantom_{}", idx),
-                ).pub_()
-                    .build_ty(phantom_ty);
-                fields.push(phantom_field);
+                    let prefix = ctx.trait_prefix();
+                    let field_name = ctx.rust_ident(format!("_phantom_{}", idx));
+                    fields.push(quote! {
+                        pub #field_name : ::#prefix::marker::PhantomData<
+                            ::#prefix::cell::UnsafeCell<#ident>
+                        > ,
+                    });
+                }
+
+                generics = quote! {
+                    < #( #param_names ),* >
+                };
             }
         }
 
-        let generics = generics.build();
-
-        let rust_struct = builder
-            .with_generics(generics.clone())
-            .with_fields(fields)
-            .build();
-        result.push(rust_struct);
+        tokens.append(quote! {
+            #generics {
+                #( #fields )*
+            }
+        });
+        result.push(tokens);
 
         // Generate the inner types and all that stuff.
         //
@@ -1765,7 +1739,7 @@ impl CodeGenerator for CompInfo {
         if self.found_unknown_attr() {
             warn!(
                 "Type {} has an unkown attribute that may affect layout",
-                canonical_name
+                canonical_ident
             );
         }
 
@@ -1779,14 +1753,15 @@ impl CodeGenerator for CompInfo {
             if ctx.options().layout_tests {
                 if let Some(layout) = layout {
                     let fn_name =
-                        format!("bindgen_test_layout_{}", canonical_name);
-                    let fn_name = ctx.rust_ident_raw(&fn_name);
-                    let type_name = ctx.rust_ident_raw(&canonical_name);
+                        format!("bindgen_test_layout_{}", canonical_ident);
+                    let fn_name = ctx.rust_ident_raw(fn_name);
                     let prefix = ctx.trait_prefix();
-                    let size_of_expr = quote_expr!(ctx.ext_cx(),
-                                    ::$prefix::mem::size_of::<$type_name>());
-                    let align_of_expr = quote_expr!(ctx.ext_cx(),
-                                    ::$prefix::mem::align_of::<$type_name>());
+                    let size_of_expr = quote! {
+                        ::#prefix::mem::size_of::<#canonical_ident>()
+                    };
+                    let align_of_expr = quote! {
+                        ::#prefix::mem::align_of::<#canonical_ident>()
+                    };
                     let size = layout.size;
                     let align = layout.align;
 
@@ -1795,11 +1770,12 @@ impl CodeGenerator for CompInfo {
                             // FIXME when [RFC 1358](https://github.com/rust-lang/rust/issues/33626) ready
                             None
                         } else {
-                            quote_item!(ctx.ext_cx(),
-                            assert_eq!($align_of_expr,
-                                       $align,
-                                       concat!("Alignment of ", stringify!($type_name)));
-                        )
+                            Some(quote! {
+                                assert_eq!(#align_of_expr,
+                                       #align,
+                                       concat!("Alignment of ", stringify!(#canonical_ident)));
+
+                            })
                         };
 
                     // FIXME when [issue #465](https://github.com/rust-lang-nursery/rust-bindgen/issues/465) ready
@@ -1814,43 +1790,43 @@ impl CodeGenerator for CompInfo {
 
                     let check_field_offset =
                         if should_skip_field_offset_checks {
-                            None
+                            vec![]
                         } else {
                             let asserts = self.fields()
-                        .iter()
-                        .filter_map(|field| match *field {
-                            Field::DataMember(ref f) if f.name().is_some() => Some(f),
-                            _ => None,
-                        })
-                        .flat_map(|field| {
-                            let name = field.name().unwrap();
-                            field.offset().and_then(|offset| {
-                                let field_offset = offset / 8;
-                                let field_name = ctx.rust_ident(name);
-
-                                quote_item!(ctx.ext_cx(),
-                                    assert_eq!(unsafe { &(*(0 as *const $type_name)).$field_name as *const _ as usize },
-                                               $field_offset,
-                                               concat!("Alignment of field: ", stringify!($type_name), "::", stringify!($field_name)));
-                                )
-                            })
-                        })
-                        .collect::<Vec<P<ast::Item>>>();
-
-                            Some(asserts)
+                                .iter()
+                                .filter_map(|field| match *field {
+                                    Field::DataMember(ref f) if f.name().is_some() => Some(f),
+                                    _ => None,
+                                })
+                                .flat_map(|field| {
+                                    let name = field.name().unwrap();
+                                    field.offset().and_then(|offset| {
+                                        let field_offset = offset / 8;
+                                        let field_name = ctx.rust_ident(name);
+
+                                        Some(quote! {
+                                            assert_eq!(unsafe { &(*(0 as *const #canonical_ident)).#field_name as *const _ as usize },
+                                                       #field_offset,
+                                                       concat!("Alignment of field: ", stringify!(#canonical_ident), "::", stringify!(#field_name)));
+                                        })
+                                    })
+                                })
+                                .collect::<Vec<quote::Tokens>>();
+
+                            asserts
                         };
 
-                    let item = quote_item!(ctx.ext_cx(),
+                    let item = quote! {
                         #[test]
-                        fn $fn_name() {
-                            assert_eq!($size_of_expr,
-                                       $size,
-                                       concat!("Size of: ", stringify!($type_name)));
+                        fn #fn_name() {
+                            assert_eq!(#size_of_expr,
+                                       #size,
+                                       concat!("Size of: ", stringify!(#canonical_ident)));
 
-                            $check_struct_align
-                            $check_field_offset
-                        })
-                        .unwrap();
+                            #check_struct_align
+                            #( #check_field_offset )*
+                        }
+                    };
                     result.push(item);
                 }
             }
@@ -1907,63 +1883,25 @@ impl CodeGenerator for CompInfo {
 
         // NB: We can't use to_rust_ty here since for opaque types this tries to
         // use the specialization knowledge to generate a blob field.
-        let ty_for_impl = aster::AstBuilder::new()
-            .ty()
-            .path()
-            .segment(&canonical_name)
-            .with_generics(generics.clone())
-            .build()
-            .build();
+        let ty_for_impl = quote! {
+            #canonical_ident #generics
+        };
 
         if needs_clone_impl {
-            let impl_ = quote_item!(ctx.ext_cx(),
-                impl X {
+            result.push(quote! {
+                impl #generics Clone for #ty_for_impl {
                     fn clone(&self) -> Self { *self }
                 }
-            );
-
-            let impl_ = match impl_.unwrap().node {
-                ast::ItemKind::Impl(_, _, _, _, _, ref items) => items.clone(),
-                _ => unreachable!(),
-            };
-
-            let clone_impl = aster::AstBuilder::new()
-                .item()
-                .impl_()
-                .trait_()
-                .id("Clone")
-                .build()
-                .with_generics(generics.clone())
-                .with_items(impl_)
-                .build_ty(ty_for_impl.clone());
-
-            result.push(clone_impl);
+            });
         }
 
         if needs_default_impl {
             let prefix = ctx.trait_prefix();
-            let impl_ = quote_item!(ctx.ext_cx(),
-                impl X {
-                    fn default() -> Self { unsafe { ::$prefix::mem::zeroed() } }
+            result.push(quote! {
+                impl #generics Default for #ty_for_impl {
+                    fn default() -> Self { unsafe { ::#prefix::mem::zeroed() } }
                 }
-            );
-
-            let impl_ = match impl_.unwrap().node {
-                ast::ItemKind::Impl(_, _, _, _, _, ref items) => items.clone(),
-                _ => unreachable!(),
-            };
-
-            let default_impl = aster::AstBuilder::new()
-                .item()
-                .impl_()
-                .trait_()
-                .id("Default")
-                .build()
-                .with_generics(generics.clone())
-                .with_items(impl_)
-                .build_ty(ty_for_impl.clone());
-
-            result.push(default_impl);
+            });
         }
 
         if needs_debug_impl {
@@ -1974,27 +1912,19 @@ impl CodeGenerator for CompInfo {
                 self.kind(),
             );
 
-            let debug_impl = aster::AstBuilder::new()
-                .item()
-                .impl_()
-                .trait_()
-                .id("::std::fmt::Debug")
-                .build()
-                .with_generics(generics.clone())
-                .with_items(impl_)
-                .build_ty(ty_for_impl.clone());
-
-            result.push(debug_impl);
+            result.push(quote! {
+                impl #generics ::std::fmt::Debug for #ty_for_impl {
+                    #impl_
+                }
+            });
         }
 
         if !methods.is_empty() {
-            let methods = aster::AstBuilder::new()
-                .item()
-                .impl_()
-                .with_generics(generics)
-                .with_items(methods)
-                .build_ty(ty_for_impl);
-            result.push(methods);
+            result.push(quote! {
+                impl #generics #ty_for_impl {
+                    #( #methods )*
+                }
+            });
         }
     }
 }
@@ -2003,7 +1933,7 @@ trait MethodCodegen {
     fn codegen_method<'a>(
         &self,
         ctx: &BindgenContext,
-        methods: &mut Vec<ast::ImplItem>,
+        methods: &mut Vec<quote::Tokens>,
         method_names: &mut HashMap<String, usize>,
         result: &mut CodegenResult<'a>,
         parent: &CompInfo,
@@ -2014,7 +1944,7 @@ impl MethodCodegen for Method {
     fn codegen_method<'a>(
         &self,
         ctx: &BindgenContext,
-        methods: &mut Vec<ast::ImplItem>,
+        methods: &mut Vec<quote::Tokens>,
         method_names: &mut HashMap<String, usize>,
         result: &mut CodegenResult<'a>,
         _parent: &CompInfo,
@@ -2067,45 +1997,15 @@ impl MethodCodegen for Method {
             name.push_str(&count.to_string());
         }
 
-        let function_name = function_item.canonical_name(ctx);
-        let mut fndecl = utils::rust_fndecl_from_signature(ctx, signature_item)
-            .unwrap();
+        let function_name = ctx.rust_ident(function_item.canonical_name(ctx));
+        let mut args = utils::fnsig_arguments(ctx, signature);
+        let mut ret = utils::fnsig_return_ty(ctx, signature);
+
         if !self.is_static() && !self.is_constructor() {
-            let mutability = if self.is_const() {
-                ast::Mutability::Immutable
+            args[0] = if self.is_const() {
+                quote! { &self }
             } else {
-                ast::Mutability::Mutable
-            };
-
-            assert!(!fndecl.inputs.is_empty());
-
-            // FIXME: use aster here.
-            fndecl.inputs[0] = ast::Arg {
-                ty: P(ast::Ty {
-                    id: ast::DUMMY_NODE_ID,
-                    node: ast::TyKind::Rptr(
-                        None,
-                        ast::MutTy {
-                            ty: P(ast::Ty {
-                                id: ast::DUMMY_NODE_ID,
-                                node: ast::TyKind::ImplicitSelf,
-                                span: ctx.span(),
-                            }),
-                            mutbl: mutability,
-                        },
-                    ),
-                    span: ctx.span(),
-                }),
-                pat: P(ast::Pat {
-                    id: ast::DUMMY_NODE_ID,
-                    node: ast::PatKind::Ident(
-                        ast::BindingMode::ByValue(ast::Mutability::Immutable),
-                        respan(ctx.span(), ctx.ext_cx().ident_of("self")),
-                        None,
-                    ),
-                    span: ctx.span(),
-                }),
-                id: ast::DUMMY_NODE_ID,
+                quote! { &mut self }
             };
         }
 
@@ -2115,19 +2015,10 @@ impl MethodCodegen for Method {
         // Note that constructors in Clang are represented as functions with
         // return-type = void.
         if self.is_constructor() {
-            fndecl.inputs.remove(0);
-            fndecl.output =
-                ast::FunctionRetTy::Ty(quote_ty!(ctx.ext_cx(), Self));
+            args.remove(0);
+            ret = quote! { -> Self };
         }
 
-        let sig = ast::MethodSig {
-            unsafety: ast::Unsafety::Unsafe,
-            abi: abi::Abi::Rust,
-            decl: P(fndecl),
-            generics: ast::Generics::default(),
-            constness: respan(ctx.span(), ast::Constness::NotConst),
-        };
-
         let mut exprs =
             helpers::ast_ty::arguments_from_signature(&signature, ctx);
 
@@ -2138,67 +2029,60 @@ impl MethodCodegen for Method {
         if self.is_constructor() {
             let prefix = ctx.trait_prefix();
             let tmp_variable_decl =
-                quote_stmt!(ctx.ext_cx(),
-                            let mut __bindgen_tmp = ::$prefix::mem::uninitialized())
-                .unwrap();
+                quote! {
+                    let mut __bindgen_tmp = ::#prefix::mem::uninitialized()
+                };
             stmts.push(tmp_variable_decl);
-            exprs[0] = quote_expr!(ctx.ext_cx(), &mut __bindgen_tmp);
+            exprs[0] = quote! {
+                &mut __bindgen_tmp
+            };
         } else if !self.is_static() {
             assert!(!exprs.is_empty());
-            exprs[0] = quote_expr!(ctx.ext_cx(), self);
+            exprs[0] = quote! {
+                self
+            };
         };
 
-        let call = aster::expr::ExprBuilder::new()
-            .call()
-            .id(function_name)
-            .with_args(exprs)
-            .build();
+        let call = quote! {
+            #function_name (#( #exprs ),* )
+        };
 
-        stmts.push(ast::Stmt {
-            id: ast::DUMMY_NODE_ID,
-            node: ast::StmtKind::Expr(call),
-            span: ctx.span(),
-        });
+        stmts.push(call);
 
         if self.is_constructor() {
-            stmts.push(quote_stmt!(ctx.ext_cx(), __bindgen_tmp).unwrap());
+            stmts.push(quote! {
+                __bindgen_tmp
+            });
         }
 
-        let block = ast::Block {
-            stmts: stmts,
-            id: ast::DUMMY_NODE_ID,
-            rules: ast::BlockCheckMode::Default,
-            span: ctx.span(),
+        let block = quote! {
+            #( #stmts );*
         };
 
         let mut attrs = vec![];
         attrs.push(attributes::inline());
 
-        let item = ast::ImplItem {
-            id: ast::DUMMY_NODE_ID,
-            ident: ctx.rust_ident(&name),
-            vis: ast::Visibility::Public,
-            attrs: attrs,
-            node: ast::ImplItemKind::Method(sig, P(block)),
-            defaultness: ast::Defaultness::Final,
-            span: ctx.span(),
-        };
-
-        methods.push(item);
+        let name = ctx.rust_ident(&name);
+        methods.push(quote! {
+            #[inline]
+            pub unsafe fn #name ( #( #args ),* ) #ret {
+                #block
+            }
+        });
     }
 }
 
 /// A helper type to construct enums, either bitfield ones or rust-style ones.
 enum EnumBuilder<'a> {
-    Rust(aster::item::ItemEnumBuilder<aster::invoke::Identity>),
+    Rust(quote::Tokens),
     Bitfield {
         canonical_name: &'a str,
-        aster: P<ast::Item>,
+        tokens: quote::Tokens,
     },
-    Consts { aster: P<ast::Item> },
+    Consts(Vec<quote::Tokens>),
     ModuleConsts {
         module_name: &'a str,
-        module_items: Vec<P<ast::Item>>,
+        module_items: Vec<quote::Tokens>,
     },
 }
 
@@ -2206,41 +2090,47 @@ impl<'a> EnumBuilder<'a> {
     /// Create a new enum given an item builder, a canonical name, a name for
     /// the representation, and whether it should be represented as a rust enum.
     fn new(
-        aster: aster::item::ItemBuilder<aster::invoke::Identity>,
         name: &'a str,
-        repr: P<ast::Ty>,
+        attrs: Vec<quote::Tokens>,
+        repr: quote::Tokens,
         bitfield_like: bool,
         constify: bool,
         constify_module: bool,
     ) -> Self {
+        let ident = quote::Ident::new(name);
         if bitfield_like {
             EnumBuilder::Bitfield {
                 canonical_name: name,
-                aster: aster
-                    .tuple_struct(name)
-                    .field()
-                    .pub_()
-                    .build_ty(repr)
-                    .build(),
+                tokens: quote! {
+                    #( #attrs )*
+                    pub struct #ident (pub #repr);
+                },
             }
         } else if constify {
             if constify_module {
-                let type_definition = aster::item::ItemBuilder::new()
-                    .pub_()
-                    .type_(CONSTIFIED_ENUM_MODULE_REPR_NAME)
-                    .build_ty(repr);
+                let ident = quote::Ident::new(CONSTIFIED_ENUM_MODULE_REPR_NAME);
+                let type_definition = quote! {
+                    pub type #ident = #repr;
+                };
 
                 EnumBuilder::ModuleConsts {
                     module_name: name,
                     module_items: vec![type_definition],
                 }
             } else {
-                EnumBuilder::Consts {
-                    aster: aster.type_(name).build_ty(repr),
-                }
+                EnumBuilder::Consts(vec![
+                    quote! {
+                        pub type #ident = #repr;
+                    }
+                ])
             }
         } else {
-            EnumBuilder::Rust(aster.enum_(name))
+            let mut tokens = quote! {
+                #( #attrs )*
+                pub enum #ident
+            };
+            tokens.append("{");
+            EnumBuilder::Rust(tokens)
         }
     }
 
@@ -2250,28 +2140,25 @@ impl<'a> EnumBuilder<'a> {
         ctx: &BindgenContext,
         variant: &EnumVariant,
         mangling_prefix: Option<&String>,
-        rust_ty: P<ast::Ty>,
+        rust_ty: quote::Tokens,
         result: &mut CodegenResult<'b>,
     ) -> Self {
         let variant_name = ctx.rust_mangle(variant.name());
-        let expr = aster::AstBuilder::new().expr();
         let expr = match variant.val() {
             EnumVariantValue::Signed(v) => helpers::ast_ty::int_expr(v),
-            EnumVariantValue::Unsigned(v) => expr.uint(v),
+            EnumVariantValue::Unsigned(v) => helpers::ast_ty::uint_expr(v),
         };
 
         match self {
-            EnumBuilder::Rust(b) => {
-                EnumBuilder::Rust(b.with_variant_(ast::Variant_ {
-                    name: ctx.rust_ident(&*variant_name),
-                    attrs: vec![],
-                    data: ast::VariantData::Unit(ast::DUMMY_NODE_ID),
-                    disr_expr: Some(expr),
-                }))
+            EnumBuilder::Rust(tokens) => {
+                let name = ctx.rust_ident(variant_name);
+                EnumBuilder::Rust(quote! {
+                    #tokens
+                    #name = #expr,
+                })
             }
-            EnumBuilder::Bitfield {
-                canonical_name, ..
-            } => {
+
+            EnumBuilder::Bitfield { .. } => {
                 let constant_name = match mangling_prefix {
                     Some(prefix) => {
                         Cow::Owned(format!("{}_{}", prefix, variant_name))
@@ -2279,20 +2166,14 @@ impl<'a> EnumBuilder<'a> {
                     None => variant_name,
                 };
 
-                let constant = aster::AstBuilder::new()
-                    .item()
-                    .pub_()
-                    .const_(&*constant_name)
-                    .expr()
-                    .call()
-                    .id(canonical_name)
-                    .arg()
-                    .build(expr)
-                    .build()
-                    .build(rust_ty);
-                result.push(constant);
+                let ident = ctx.rust_ident(constant_name);
+                result.push(quote! {
+                    pub const #ident : #rust_ty = #rust_ty ( #expr );
+                });
+
                 self
             }
+
             EnumBuilder::Consts {
                 ..
             } => {
@@ -2303,37 +2184,22 @@ impl<'a> EnumBuilder<'a> {
                     None => variant_name,
                 };
 
-                let constant = aster::AstBuilder::new()
-                    .item()
-                    .pub_()
-                    .const_(&*constant_name)
-                    .expr()
-                    .build(expr)
-                    .build(rust_ty);
+                let ident = ctx.rust_ident(constant_name);
+                result.push(quote! {
+                    pub const #ident : #rust_ty = #expr ;
+                });
 
-                result.push(constant);
                 self
             }
             EnumBuilder::ModuleConsts {
                 module_name,
-                module_items,
-                ..
+                mut module_items,
             } => {
-                // Variant type
-                let inside_module_type = aster::AstBuilder::new().ty().id(
-                    CONSTIFIED_ENUM_MODULE_REPR_NAME,
-                );
-
-                let constant = aster::AstBuilder::new()
-                    .item()
-                    .pub_()
-                    .const_(&*variant_name)
-                    .expr()
-                    .build(expr)
-                    .build(inside_module_type.clone());
-
-                let mut module_items = module_items.clone();
-                module_items.push(constant);
+                let name = ctx.rust_ident(variant_name);
+                let ty = ctx.rust_ident(CONSTIFIED_ENUM_MODULE_REPR_NAME);
+                module_items.push(quote! {
+                    pub const #name : #ty = #expr ;
+                });
 
                 EnumBuilder::ModuleConsts {
                     module_name,
@@ -2346,86 +2212,74 @@ impl<'a> EnumBuilder<'a> {
     fn build<'b>(
         self,
         ctx: &BindgenContext,
-        rust_ty: P<ast::Ty>,
+        rust_ty: quote::Tokens,
         result: &mut CodegenResult<'b>,
-    ) -> P<ast::Item> {
+    ) -> quote::Tokens {
         match self {
-            EnumBuilder::Rust(b) => b.build(),
+            EnumBuilder::Rust(mut t) => {
+                t.append("}");
+                t
+            }
             EnumBuilder::Bitfield {
                 canonical_name,
-                aster,
+                tokens,
             } => {
                 let rust_ty_name = ctx.rust_ident_raw(canonical_name);
                 let prefix = ctx.trait_prefix();
 
-                let impl_ = quote_item!(ctx.ext_cx(),
-                    impl ::$prefix::ops::BitOr<$rust_ty> for $rust_ty {
+                result.push(quote! {
+                    impl ::#prefix::ops::BitOr<#rust_ty> for #rust_ty {
                         type Output = Self;
 
                         #[inline]
                         fn bitor(self, other: Self) -> Self {
-                            $rust_ty_name(self.0 | other.0)
+                            #rust_ty_name(self.0 | other.0)
                         }
                     }
-                ).unwrap();
-                result.push(impl_);
+                });
 
-                let impl_ = quote_item!(ctx.ext_cx(),
-                    impl ::$prefix::ops::BitOrAssign for $rust_ty {
+                result.push(quote! {
+                    impl ::#prefix::ops::BitOrAssign for #rust_ty {
                         #[inline]
-                        fn bitor_assign(&mut self, rhs: $rust_ty) {
+                        fn bitor_assign(&mut self, rhs: #rust_ty) {
                             self.0 |= rhs.0;
                         }
                     }
-                ).unwrap();
-                result.push(impl_);
+                });
 
-                let impl_ = quote_item!(ctx.ext_cx(),
-                    impl ::$prefix::ops::BitAnd<$rust_ty> for $rust_ty {
+                result.push(quote! {
+                    impl ::#prefix::ops::BitAnd<#rust_ty> for #rust_ty {
                         type Output = Self;
 
                         #[inline]
                         fn bitand(self, other: Self) -> Self {
-                            $rust_ty_name(self.0 & other.0)
+                            #rust_ty_name(self.0 & other.0)
                         }
                     }
-                ).unwrap();
-                result.push(impl_);
+                });
 
-                let impl_ = quote_item!(ctx.ext_cx(),
-                    impl ::$prefix::ops::BitAndAssign for $rust_ty {
+                result.push(quote! {
+                    impl ::#prefix::ops::BitAndAssign for #rust_ty {
                         #[inline]
-                        fn bitand_assign(&mut self, rhs: $rust_ty) {
+                        fn bitand_assign(&mut self, rhs: #rust_ty) {
                             self.0 &= rhs.0;
                         }
                     }
-                ).unwrap();
-                result.push(impl_);
+                });
 
-                aster
+                tokens
             }
-            EnumBuilder::Consts {
-                aster, ..
-            } => aster,
+            EnumBuilder::Consts(tokens) => quote! { #( #tokens )* },
             EnumBuilder::ModuleConsts {
                 module_items,
                 module_name,
-                ..
             } => {
-                // Create module item with type and variant definitions
-                let module_item = P(ast::Item {
-                    ident: ast::Ident::from_str(module_name),
-                    attrs: vec![],
-                    id: ast::DUMMY_NODE_ID,
-                    node: ast::ItemKind::Mod(ast::Mod {
-                        inner: DUMMY_SP,
-                        items: module_items,
-                    }),
-                    vis: ast::Visibility::Public,
-                    span: DUMMY_SP,
-                });
-
-                module_item
+                let ident = ctx.rust_ident(module_name);
+                quote! {
+                    pub mod #ident {
+                        #( #module_items )*
+                    }
+                }
             }
         }
     }
@@ -2444,6 +2298,7 @@ impl CodeGenerator for Enum {
         debug_assert!(item.is_enabled_for_codegen(ctx));
 
         let name = item.canonical_name(ctx);
+        let ident = ctx.rust_ident(&name);
         let enum_ty = item.expect_type();
         let layout = enum_ty.layout(ctx);
 
@@ -2485,8 +2340,6 @@ impl CodeGenerator for Enum {
             }
         };
 
-        let mut builder = aster::AstBuilder::new().item().pub_();
-
         // FIXME(emilio): These should probably use the path so it can
         // disambiguate between namespaces, just like is_opaque etc.
         let is_bitfield = {
@@ -2511,42 +2364,41 @@ impl CodeGenerator for Enum {
 
         let is_rust_enum = !is_bitfield && !is_constified_enum;
 
+        let mut attrs = vec![];
+
         // FIXME: Rust forbids repr with empty enums. Remove this condition when
         // this is allowed.
         //
         // TODO(emilio): Delegate this to the builders?
         if is_rust_enum {
             if !self.variants().is_empty() {
-                builder = builder.with_attr(attributes::repr(repr_name));
+                attrs.push(attributes::repr(repr_name));
             }
         } else if is_bitfield {
-            builder = builder.with_attr(attributes::repr("C"));
+            attrs.push(attributes::repr("C"));
         }
 
         if let Some(comment) = item.comment(ctx) {
-            builder = builder.with_attr(attributes::doc(comment));
+            attrs.push(attributes::doc(comment));
         }
 
         if !is_constified_enum {
-            let derives =
-                attributes::derives(
-                    &["Debug", "Copy", "Clone", "PartialEq", "Eq", "Hash"],
-                );
-
-            builder = builder.with_attr(derives);
+            attrs.push(attributes::derives(
+                &["Debug", "Copy", "Clone", "PartialEq", "Eq", "Hash"],
+            ));
         }
 
         fn add_constant<'a>(
             ctx: &BindgenContext,
             enum_: &Type,
             // Only to avoid recomputing every time.
-            enum_canonical_name: &str,
+            enum_canonical_name: &quote::Ident,
             // May be the same as "variant" if it's because the
             // enum is unnamed and we still haven't seen the
             // value.
             variant_name: &str,
-            referenced_name: &str,
-            enum_rust_ty: P<ast::Ty>,
+            referenced_name: &quote::Ident,
+            enum_rust_ty: quote::Tokens,
             result: &mut CodegenResult<'a>,
         ) {
             let constant_name = if enum_.name().is_some() {
@@ -2558,17 +2410,12 @@ impl CodeGenerator for Enum {
             } else {
                 variant_name.into()
             };
+            let constant_name = ctx.rust_ident(constant_name);
 
-            let constant = aster::AstBuilder::new()
-                .item()
-                .pub_()
-                .const_(constant_name)
-                .expr()
-                .path()
-                .ids(&[&*enum_canonical_name, referenced_name])
-                .build()
-                .build(enum_rust_ty);
-            result.push(constant);
+            result.push(quote! {
+                pub const #constant_name : #enum_rust_ty =
+                    #enum_canonical_name :: #referenced_name ;
+            });
         }
 
         let repr =
@@ -2577,8 +2424,8 @@ impl CodeGenerator for Enum {
                 .unwrap_or_else(|| helpers::ast_ty::raw_type(ctx, repr_name));
 
         let mut builder = EnumBuilder::new(
-            builder,
             &name,
+            attrs,
             repr,
             is_bitfield,
             is_constified_enum,
@@ -2586,7 +2433,7 @@ impl CodeGenerator for Enum {
         );
 
         // A map where we keep a value -> variant relation.
-        let mut seen_values = HashMap::<_, String>::new();
+        let mut seen_values = HashMap::<_, quote::Ident>::new();
         let enum_rust_ty = item.to_rust_ty_or_opaque(ctx, &());
         let is_toplevel = item.is_toplevel(ctx);
 
@@ -2646,7 +2493,7 @@ impl CodeGenerator for Enum {
                         add_constant(
                             ctx,
                             enum_ty,
-                            &name,
+                            &ident,
                             &*mangled_name,
                             existing_variant_name,
                             enum_rust_ty.clone(),
@@ -2671,7 +2518,7 @@ impl CodeGenerator for Enum {
                         result,
                     );
 
-                    let variant_name = ctx.rust_mangle(variant.name());
+                    let variant_name = ctx.rust_ident(variant.name());
 
                     // If it's an unnamed enum, or constification is enforced,
                     // we also generate a constant so it can be properly
@@ -2685,29 +2532,33 @@ impl CodeGenerator for Enum {
                             let parent_name =
                                 parent_canonical_name.as_ref().unwrap();
 
-                            Cow::Owned(
-                                format!("{}_{}", parent_name, variant_name),
+                            quote::Ident::new(
+                                format!(
+                                    "{}_{}",
+                                    parent_name,
+                                    variant_name
+                                )
                             )
                         };
 
                         add_constant(
                             ctx,
                             enum_ty,
-                            &name,
-                            &mangled_name,
+                            &ident,
+                            mangled_name.as_ref(),
                             &variant_name,
                             enum_rust_ty.clone(),
                             result,
                         );
                     }
 
-                    entry.insert(variant_name.into_owned());
+                    entry.insert(quote::Ident::new(variant_name));
                 }
             }
         }
 
-        let enum_ = builder.build(ctx, enum_rust_ty, result);
-        result.push(enum_);
+        let item = builder.build(ctx, enum_rust_ty, result);
+        result.push(item);
     }
 }
 
@@ -2731,7 +2582,7 @@ trait TryToOpaque {
         &self,
         ctx: &BindgenContext,
         extra: &Self::Extra,
-    ) -> error::Result<P<ast::Ty>> {
+    ) -> error::Result<quote::Tokens> {
         self.try_get_layout(ctx, extra).map(|layout| {
             helpers::blob(layout)
         })
@@ -2759,7 +2610,7 @@ trait ToOpaque: TryToOpaque {
         &self,
         ctx: &BindgenContext,
         extra: &Self::Extra,
-    ) -> P<ast::Ty> {
+    ) -> quote::Tokens {
         let layout = self.get_layout(ctx, extra);
         helpers::blob(layout)
     }
@@ -2785,7 +2636,7 @@ trait TryToRustTy {
         &self,
         ctx: &BindgenContext,
         extra: &Self::Extra,
-    ) -> error::Result<P<ast::Ty>>;
+    ) -> error::Result<quote::Tokens>;
 }
 
 /// Fallible conversion to a Rust type or an opaque blob with the correct size
@@ -2800,7 +2651,7 @@ trait TryToRustTyOrOpaque: TryToRustTy + TryToOpaque {
         &self,
         ctx: &BindgenContext,
         extra: &<Self as TryToRustTyOrOpaque>::Extra,
-    ) -> error::Result<P<ast::Ty>>;
+    ) -> error::Result<quote::Tokens>;
 }
 
 impl<E, T> TryToRustTyOrOpaque for T
@@ -2814,7 +2665,7 @@ where
         &self,
         ctx: &BindgenContext,
         extra: &E,
-    ) -> error::Result<P<ast::Ty>> {
+    ) -> error::Result<quote::Tokens> {
         self.try_to_rust_ty(ctx, extra).or_else(
             |_| if let Ok(layout) =
                 self.try_get_layout(ctx, extra)
@@ -2851,7 +2702,7 @@ trait ToRustTyOrOpaque: TryToRustTy + ToOpaque {
         &self,
         ctx: &BindgenContext,
         extra: &<Self as ToRustTyOrOpaque>::Extra,
-    ) -> P<ast::Ty>;
+    ) -> quote::Tokens;
 }
 
 impl<E, T> ToRustTyOrOpaque for T
@@ -2864,7 +2715,7 @@ where
         &self,
         ctx: &BindgenContext,
         extra: &E,
-    ) -> P<ast::Ty> {
+    ) -> quote::Tokens {
         self.try_to_rust_ty(ctx, extra).unwrap_or_else(|_| {
             self.to_opaque(ctx, extra)
         })
@@ -2890,7 +2741,7 @@ impl TryToRustTy for ItemId {
         &self,
         ctx: &BindgenContext,
         _: &(),
-    ) -> error::Result<P<ast::Ty>> {
+    ) -> error::Result<quote::Tokens> {
         ctx.resolve_item(*self).try_to_rust_ty(ctx, &())
     }
 }
@@ -2914,7 +2765,7 @@ impl TryToRustTy for Item {
         &self,
         ctx: &BindgenContext,
         _: &(),
-    ) -> error::Result<P<ast::Ty>> {
+    ) -> error::Result<quote::Tokens> {
         self.kind().expect_type().try_to_rust_ty(ctx, self)
     }
 }
@@ -2938,7 +2789,7 @@ impl TryToRustTy for Type {
         &self,
         ctx: &BindgenContext,
         item: &Item,
-    ) -> error::Result<P<ast::Ty>> {
+    ) -> error::Result<quote::Tokens> {
         use self::helpers::ast_ty::*;
 
         match *self.kind() {
@@ -2946,11 +2797,11 @@ impl TryToRustTy for Type {
             // TODO: we should do something smart with nullptr, or maybe *const
             // c_void is enough?
             TypeKind::NullPtr => {
-                Ok(raw_type(ctx, "c_void").to_ptr(true, ctx.span()))
+                Ok(raw_type(ctx, "c_void").to_ptr(true))
             }
             TypeKind::Int(ik) => {
                 match ik {
-                    IntKind::Bool => Ok(aster::ty::TyBuilder::new().bool()),
+                    IntKind::Bool => Ok(quote! { bool }),
                     IntKind::Char {
                         ..
                     } => Ok(raw_type(ctx, "c_char")),
@@ -2965,25 +2816,27 @@ impl TryToRustTy for Type {
                     IntKind::LongLong => Ok(raw_type(ctx, "c_longlong")),
                     IntKind::ULongLong => Ok(raw_type(ctx, "c_ulonglong")),
 
-                    IntKind::I8 => Ok(aster::ty::TyBuilder::new().i8()),
-                    IntKind::U8 => Ok(aster::ty::TyBuilder::new().u8()),
-                    IntKind::I16 => Ok(aster::ty::TyBuilder::new().i16()),
-                    IntKind::U16 => Ok(aster::ty::TyBuilder::new().u16()),
-                    IntKind::I32 => Ok(aster::ty::TyBuilder::new().i32()),
-                    IntKind::U32 => Ok(aster::ty::TyBuilder::new().u32()),
-                    IntKind::I64 => Ok(aster::ty::TyBuilder::new().i64()),
-                    IntKind::U64 => Ok(aster::ty::TyBuilder::new().u64()),
+                    IntKind::I8 => Ok(quote! { i8 }),
+                    IntKind::U8 => Ok(quote! { u8 }),
+                    IntKind::I16 => Ok(quote! { i16 }),
+                    IntKind::U16 => Ok(quote! { u16 }),
+                    IntKind::I32 => Ok(quote! { i32 }),
+                    IntKind::U32 => Ok(quote! { u32 }),
+                    IntKind::I64 => Ok(quote! { i64 }),
+                    IntKind::U64 => Ok(quote! { u64 }),
                     IntKind::Custom {
                         name, ..
                     } => {
                         let ident = ctx.rust_ident_raw(name);
-                        Ok(quote_ty!(ctx.ext_cx(), $ident))
+                        Ok(quote! {
+                            #ident
+                        })
                     }
                     // FIXME: This doesn't generate the proper alignment, but we
                     // can't do better right now. We should be able to use
                     // i128/u128 when they're available.
                     IntKind::U128 | IntKind::I128 => {
-                        Ok(aster::ty::TyBuilder::new().array(2).u64())
+                        Ok(quote! { [u64; 2] })
                     }
                 }
             }
@@ -2993,9 +2846,13 @@ impl TryToRustTy for Type {
 
                 ctx.generated_bindegen_complex();
                 Ok(if ctx.options().enable_cxx_namespaces {
-                    quote_ty!(ctx.ext_cx(), root::__BindgenComplex<$float_path>)
+                    quote! {
+                        root::__BindgenComplex<#float_path>
+                    }
                 } else {
-                    quote_ty!(ctx.ext_cx(), __BindgenComplex<$float_path>)
+                    quote! {
+                        __BindgenComplex<#float_path>
+                    }
                 })
             }
             TypeKind::Function(ref fs) => {
@@ -3003,18 +2860,24 @@ impl TryToRustTy for Type {
                 // sizeof(NonZero<_>) optimization with opaque blobs (because
                 // they aren't NonZero), so don't *ever* use an or_opaque
                 // variant here.
-                let ty = fs.try_to_rust_ty(ctx, item)?;
+                let ty = fs.try_to_rust_ty(ctx, &())?;
 
                 let prefix = ctx.trait_prefix();
-                Ok(quote_ty!(ctx.ext_cx(), ::$prefix::option::Option<$ty>))
+                Ok(quote! {
+                    ::#prefix::option::Option<#ty>
+                })
             }
             TypeKind::Array(item, len) => {
                 let ty = item.try_to_rust_ty(ctx, &())?;
-                Ok(aster::ty::TyBuilder::new().array(len).build(ty))
+                Ok(quote! {
+                    [ #ty ; #len ]
+                })
             }
             TypeKind::Enum(..) => {
+                let mut tokens = quote! {};
                 let path = item.namespace_aware_canonical_path(ctx);
-                Ok(aster::AstBuilder::new().ty().path().ids(path).build())
+                tokens.append_separated(path.into_iter().map(quote::Ident::new), "::");
+                Ok(tokens)
             }
             TypeKind::TemplateInstantiation(ref inst) => {
                 inst.try_to_rust_ty(ctx, item)
@@ -3039,7 +2902,7 @@ impl TryToRustTy for Type {
                 {
                     Ok(ty)
                 } else {
-                    utils::build_templated_path(item, ctx, template_params)
+                    utils::build_templated_path(item, ctx, vec![]) //template_params)
                 }
             }
             TypeKind::Comp(ref info) => {
@@ -3050,48 +2913,54 @@ impl TryToRustTy for Type {
                     return self.try_to_opaque(ctx, item);
                 }
 
-                let template_params = template_params.unwrap_or(vec![]);
-                utils::build_templated_path(item, ctx, template_params)
+                // let template_params = template_params.unwrap_or(vec![]);
+                utils::build_templated_path(item, ctx, vec![])
             }
             TypeKind::Opaque => self.try_to_opaque(ctx, item),
             TypeKind::BlockPointer => {
                 let void = raw_type(ctx, "c_void");
                 Ok(void.to_ptr(
                     /* is_const = */
-                    false,
-                    ctx.span(),
+                    false
                 ))
             }
             TypeKind::Pointer(inner) |
             TypeKind::Reference(inner) => {
-                let inner = ctx.resolve_item(inner);
+                let is_const = self.is_const() || ctx.resolve_type(inner).is_const();
+
+                let inner = inner.into_resolver().through_type_refs().resolve(ctx);
                 let inner_ty = inner.expect_type();
 
                 // Regardless if we can properly represent the inner type, we
                 // should always generate a proper pointer here, so use
                 // infallible conversion of the inner type.
-                let ty = inner.to_rust_ty_or_opaque(ctx, &());
+                let mut ty = inner.to_rust_ty_or_opaque(ctx, &());
+                ty.append_implicit_template_params(ctx, inner);
 
                 // Avoid the first function pointer level, since it's already
                 // represented in Rust.
                 if inner_ty.canonical_type(ctx).is_function() {
                     Ok(ty)
                 } else {
-                    let is_const = self.is_const() ||
-                        inner.expect_type().is_const();
-                    Ok(ty.to_ptr(is_const, ctx.span()))
+                    Ok(ty.to_ptr(is_const))
                 }
             }
             TypeKind::TypeParam => {
                 let name = item.canonical_name(ctx);
                 let ident = ctx.rust_ident(&name);
-                Ok(quote_ty!(ctx.ext_cx(), $ident))
+                Ok(quote! {
+                    #ident
+                })
             }
             TypeKind::ObjCSel => {
-                Ok(quote_ty!(ctx.ext_cx(), objc::runtime::Sel))
+                Ok(quote! {
+                    objc::runtime::Sel
+                })
             }
             TypeKind::ObjCId |
-            TypeKind::ObjCInterface(..) => Ok(quote_ty!(ctx.ext_cx(), id)),
+            TypeKind::ObjCInterface(..) => Ok(quote! {
+                id
+            }),
             ref u @ TypeKind::UnresolvedTypeRef(..) => {
                 unreachable!("Should have been resolved after parsing {:?}!", u)
             }
@@ -3120,108 +2989,81 @@ impl TryToRustTy for TemplateInstantiation {
         &self,
         ctx: &BindgenContext,
         item: &Item,
-    ) -> error::Result<P<ast::Ty>> {
+    ) -> error::Result<quote::Tokens> {
         if self.is_opaque(ctx, item) {
             return Err(error::Error::InstantiationOfOpaqueType);
         }
 
-        let decl = self.template_definition();
-        let mut ty = decl.try_to_rust_ty(ctx, &())?.unwrap();
+        let def = self.template_definition()
+            .into_resolver()
+            .through_type_refs()
+            .resolve(ctx);
 
-        let decl_params = match decl.self_template_params(ctx) {
+        let mut ty = quote! {};
+        let def_path = def.namespace_aware_canonical_path(ctx);
+        ty.append_separated(def_path.into_iter().map(|p| ctx.rust_ident(p)), "::");
+
+        let def_params = match def.self_template_params(ctx) {
             Some(params) => params,
             None => {
                 // This can happen if we generated an opaque type for a partial
                 // template specialization, and we've hit an instantiation of
                 // that partial specialization.
                 extra_assert!(
-                    decl.into_resolver()
-                        .through_type_refs()
-                        .resolve(ctx)
-                        .is_opaque(ctx, &())
+                    def.is_opaque(ctx, &())
                 );
                 return Err(error::Error::InstantiationOfOpaqueType);
             }
         };
 
-        // TODO: If the decl type is a template class/struct
-        // declaration's member template declaration, it could rely on
+        // TODO: If the definition type is a template class/struct
+        // definition's member template definition, it could rely on
         // generic template parameters from its outer template
         // class/struct. When we emit bindings for it, it could require
         // *more* type arguments than we have here, and we will need to
         // reconstruct them somehow. We don't have any means of doing
         // that reconstruction at this time.
 
-        if let ast::TyKind::Path(_, ref mut path) = ty.node {
-            let template_args = self.template_arguments()
-                .iter()
-                .zip(decl_params.iter())
-                // Only pass type arguments for the type parameters that
-                // the decl uses.
-                .filter(|&(_, param)| ctx.uses_template_parameter(decl, *param))
-                .map(|(arg, _)| arg.try_to_rust_ty(ctx, &()))
-                .collect::<error::Result<Vec<_>>>()?;
-
-            path.segments.last_mut().unwrap().parameters =
-                if template_args.is_empty() {
-                    None
-                } else {
-                    Some(P(ast::PathParameters::AngleBracketed(
-                        ast::AngleBracketedParameterData {
-                            lifetimes: vec![],
-                            types: template_args,
-                            bindings: vec![],
-                        },
-                    )))
-                }
+        let template_args = self.template_arguments()
+            .iter()
+            .zip(def_params.iter())
+        // Only pass type arguments for the type parameters that
+        // the def uses.
+            .filter(|&(_, param)| ctx.uses_template_parameter(def.id(), *param))
+            .map(|(arg, _)| {
+                let arg = arg.into_resolver().through_type_refs().resolve(ctx);
+                let mut ty = arg.try_to_rust_ty(ctx, &())?;
+                ty.append_implicit_template_params(ctx, arg);
+                Ok(ty)
+            })
+            .collect::<error::Result<Vec<_>>>()?;
+
+        if template_args.is_empty() {
+            return Ok(ty);
         }
 
-        Ok(P(ty))
+        Ok(quote! {
+            #ty < #( #template_args ),* >
+        })
     }
 }
 
 impl TryToRustTy for FunctionSig {
-    type Extra = Item;
+    type Extra = ();
 
     fn try_to_rust_ty(
         &self,
         ctx: &BindgenContext,
-        item: &Item,
-    ) -> error::Result<P<ast::Ty>> {
+        _: &(),
+    ) -> error::Result<quote::Tokens> {
         // TODO: we might want to consider ignoring the reference return value.
         let ret = utils::fnsig_return_ty(ctx, &self);
         let arguments = utils::fnsig_arguments(ctx, &self);
+        let abi = self.abi();
 
-        let decl = P(ast::FnDecl {
-            inputs: arguments,
-            output: ret,
-            variadic: self.is_variadic(),
-        });
-
-        let abi = match self.abi() {
-            Abi::Known(abi) => abi,
-            Abi::Unknown(unknown_abi) => {
-                panic!(
-                    "Invalid or unknown abi {:?} for function {:?} {:?}",
-                    unknown_abi,
-                    item.canonical_name(ctx),
-                    self
-                );
-            }
-        };
-
-        let fnty = ast::TyKind::BareFn(P(ast::BareFnTy {
-            unsafety: ast::Unsafety::Unsafe,
-            abi: abi,
-            lifetimes: vec![],
-            decl: decl,
-        }));
-
-        Ok(P(ast::Ty {
-            id: ast::DUMMY_NODE_ID,
-            node: fnty,
-            span: ctx.span(),
-        }))
+        Ok(quote! {
+            unsafe extern #abi fn ( #( #arguments ),* ) #ret
+        })
     }
 }
 
@@ -3270,7 +3112,8 @@ impl CodeGenerator for Function {
             _ => panic!("Signature kind is not a Function: {:?}", signature),
         };
 
-        let fndecl = utils::rust_fndecl_from_signature(ctx, signature_item);
+        let args = utils::fnsig_arguments(ctx, signature);
+        let ret = utils::fnsig_return_ty(ctx, signature);
 
         let mut attributes = vec![];
 
@@ -3284,9 +3127,6 @@ impl CodeGenerator for Function {
             attributes.push(attributes::link_name(name));
         }
 
-        let foreign_item_kind =
-            ast::ForeignItemKind::Fn(fndecl, ast::Generics::default());
-
         // Handle overloaded functions by giving each overload its own unique
         // suffix.
         let times_seen = result.overload_number(&canonical_name);
@@ -3294,17 +3134,7 @@ impl CodeGenerator for Function {
             write!(&mut canonical_name, "{}", times_seen).unwrap();
         }
 
-        let foreign_item = ast::ForeignItem {
-            ident: ctx.rust_ident_raw(&canonical_name),
-            attrs: attributes,
-            node: foreign_item_kind,
-            id: ast::DUMMY_NODE_ID,
-            span: ctx.span(),
-            vis: ast::Visibility::Public,
-        };
-
         let abi = match signature.abi() {
-            Abi::Known(abi) => abi,
             Abi::Unknown(unknown_abi) => {
                 panic!(
                     "Invalid or unknown abi {:?} for function {:?} ({:?})",
@@ -3313,13 +3143,29 @@ impl CodeGenerator for Function {
                     self
                 );
             }
+            abi => abi,
         };
 
-        let item = ForeignModBuilder::new(abi)
-            .with_foreign_item(foreign_item)
-            .build(ctx);
+        let variadic = if signature.is_variadic() {
+            quote! { ... }
+        } else {
+            quote! {}
+        };
 
-        result.push(item);
+        let ident = ctx.rust_ident(canonical_name);
+        let mut tokens = quote! { extern #abi };
+        tokens.append("{\n");
+        if !attributes.is_empty() {
+            tokens.append_separated(attributes, "\n");
+            tokens.append("\n");
+        }
+        let mut args = args;
+        args.push(variadic);
+        tokens.append(quote! {
+            pub fn #ident ( #( #args ),* ) #ret;
+        });
+        tokens.append("\n}");
+        result.push(tokens);
     }
 }
 
@@ -3329,86 +3175,53 @@ fn objc_method_codegen(
     method: &ObjCMethod,
     class_name: Option<&str>,
     prefix: &str,
-) -> (ast::ImplItem, ast::TraitItem) {
+) -> (quote::Tokens, quote::Tokens) {
     let signature = method.signature();
     let fn_args = utils::fnsig_arguments(ctx, signature);
     let fn_ret = utils::fnsig_return_ty(ctx, signature);
 
     let sig = if method.is_class_method() {
-        aster::AstBuilder::new()
-            .method_sig()
-            .unsafe_()
-            .fn_decl()
-            .with_args(fn_args.clone())
-            .build(fn_ret)
+        let fn_args = fn_args.clone();
+        quote! {
+            ( #( #fn_args ),* ) #fn_ret
+        }
     } else {
-        aster::AstBuilder::new()
-            .method_sig()
-            .unsafe_()
-            .fn_decl()
-            .self_()
-            .build(ast::SelfKind::Value(ast::Mutability::Immutable))
-            .with_args(fn_args.clone())
-            .build(fn_ret)
+        let fn_args = fn_args.clone();
+        let args = iter::once(quote! { self })
+            .chain(fn_args.into_iter());
+        quote! {
+            ( #( #args ),* ) #fn_ret
+        }
     };
 
-    // Collect the actual used argument names
-    let arg_names: Vec<_> = fn_args
-        .iter()
-        .map(|ref arg| match arg.pat.node {
-            ast::PatKind::Ident(_, ref spanning, _) => {
-                spanning.node.name.as_str().to_string()
-            }
-            _ => {
-                panic!("odd argument!");
-            }
-        })
-        .collect();
-
-    let methods_and_args =
-        ctx.rust_ident(&method.format_method_call(&arg_names));
+    let methods_and_args = method.format_method_call(&fn_args);
 
     let body = if method.is_class_method() {
         let class_name = class_name
             .expect("Generating a class method without class name?")
             .to_owned();
         let expect_msg = format!("Couldn't find {}", class_name);
-        quote_stmt!(ctx.ext_cx(),
-                    msg_send![objc::runtime::Class::get($class_name).expect($expect_msg), $methods_and_args])
-            .unwrap()
+        quote! {
+            msg_send!(objc::runtime::Class::get(#class_name).expect(#expect_msg), #methods_and_args)
+        }
     } else {
-        quote_stmt!(ctx.ext_cx(), msg_send![self, $methods_and_args]).unwrap()
-    };
-    let block = ast::Block {
-        stmts: vec![body],
-        id: ast::DUMMY_NODE_ID,
-        rules: ast::BlockCheckMode::Default,
-        span: ctx.span(),
-    };
-
-    let attrs = vec![];
-
-    let method_name = format!("{}{}", prefix, method.rust_name());
-
-    let impl_item = ast::ImplItem {
-        id: ast::DUMMY_NODE_ID,
-        ident: ctx.rust_ident(&method_name),
-        vis: ast::Visibility::Inherited, // Public,
-        attrs: attrs.clone(),
-        node: ast::ImplItemKind::Method(sig.clone(), P(block)),
-        defaultness: ast::Defaultness::Final,
-        span: ctx.span(),
+        quote! {
+            msg_send!(self, #methods_and_args)
+        }
     };
 
-    let trait_item = ast::TraitItem {
-        id: ast::DUMMY_NODE_ID,
-        ident: ctx.rust_ident(&method_name),
-        attrs: attrs,
-        node: ast::TraitItemKind::Method(sig, None),
-        span: ctx.span(),
-    };
+    let method_name = ctx.rust_ident(format!("{}{}", prefix, method.rust_name()));
 
-    (impl_item, trait_item)
+    (
+        quote! {
+            unsafe fn #method_name #sig {
+                #body
+            }
+        },
+        quote! {
+            unsafe fn #method_name #sig ;
+        }
+    )
 }
 
 impl CodeGenerator for ObjCInterface {
@@ -3440,7 +3253,6 @@ impl CodeGenerator for ObjCInterface {
             .collect();
 
         for class_method in self.class_methods() {
-
             let ambiquity =
                 instance_method_names.contains(&class_method.rust_name());
             let prefix = if ambiquity { "class_" } else { "" };
@@ -3454,24 +3266,22 @@ impl CodeGenerator for ObjCInterface {
             trait_items.push(trait_item)
         }
 
-        let trait_name = self.rust_name();
+        let trait_name = ctx.rust_ident(self.rust_name());
 
-        let trait_block = aster::AstBuilder::new()
-            .item()
-            .pub_()
-            .trait_(&trait_name)
-            .with_items(trait_items)
-            .build();
+        let trait_block = quote! {
+            pub trait #trait_name {
+                #( #trait_items )*
+            }
+        };
 
-        let ty_for_impl = quote_ty!(ctx.ext_cx(), id);
-        let impl_block = aster::AstBuilder::new()
-            .item()
-            .impl_()
-            .trait_()
-            .id(&trait_name)
-            .build()
-            .with_items(impl_items)
-            .build_ty(ty_for_impl);
+        let ty_for_impl = quote! {
+            id
+        };
+        let impl_block = quote! {
+            impl #trait_name for #ty_for_impl {
+                #( #impl_items )*
+            }
+        };
 
         result.push(trait_block);
         result.push(impl_block);
@@ -3479,7 +3289,7 @@ impl CodeGenerator for ObjCInterface {
     }
 }
 
-pub fn codegen(context: &mut BindgenContext) -> Vec<P<ast::Item>> {
+pub fn codegen(context: &mut BindgenContext) -> Vec<quote::Tokens> {
     context.gen(|context| {
         let _t = context.timer("codegen");
         let counter = Cell::new(0);
@@ -3511,35 +3321,32 @@ pub fn codegen(context: &mut BindgenContext) -> Vec<P<ast::Item>> {
 
 mod utils {
     use super::{ToRustTyOrOpaque, TryToRustTy, error};
-    use aster;
     use ir::context::{BindgenContext, ItemId};
     use ir::function::FunctionSig;
     use ir::item::{Item, ItemCanonicalPath};
     use ir::ty::TypeKind;
+    use quote;
     use std::mem;
-    use syntax::ast;
-    use syntax::ptr::P;
 
     pub fn prepend_objc_header(
         ctx: &BindgenContext,
-        result: &mut Vec<P<ast::Item>>,
+        result: &mut Vec<quote::Tokens>,
     ) {
         let use_objc = if ctx.options().objc_extern_crate {
-            quote_item!(ctx.ext_cx(),
+            quote! {
                 #[macro_use]
                 extern crate objc;
-            ).unwrap()
+            }
         } else {
-            quote_item!(ctx.ext_cx(),
+            quote! {
                 use objc;
-            ).unwrap()
+            }
         };
 
-
-        let id_type = quote_item!(ctx.ext_cx(),
+        let id_type = quote! {
             #[allow(non_camel_case_types)]
             pub type id = *mut objc::runtime::Object;
-        ).unwrap();
+        };
 
         let items = vec![use_objc, id_type];
         let old_items = mem::replace(result, items);
@@ -3548,90 +3355,88 @@ mod utils {
 
     pub fn prepend_union_types(
         ctx: &BindgenContext,
-        result: &mut Vec<P<ast::Item>>,
+        result: &mut Vec<quote::Tokens>,
     ) {
         let prefix = ctx.trait_prefix();
 
         // TODO(emilio): The fmt::Debug impl could be way nicer with
         // std::intrinsics::type_name, but...
-        let union_field_decl = quote_item!(ctx.ext_cx(),
+        let union_field_decl = quote! {
             #[repr(C)]
-            pub struct __BindgenUnionField<T>(
-                ::$prefix::marker::PhantomData<T>);
-        ).unwrap();
+            pub struct __BindgenUnionField<T>(::#prefix::marker::PhantomData<T>);
+        };
 
-        let union_field_impl = quote_item!(&ctx.ext_cx(),
+        let union_field_impl = quote! {
             impl<T> __BindgenUnionField<T> {
                 #[inline]
                 pub fn new() -> Self {
-                    __BindgenUnionField(::$prefix::marker::PhantomData)
+                    __BindgenUnionField(::#prefix::marker::PhantomData)
                 }
 
                 #[inline]
                 pub unsafe fn as_ref(&self) -> &T {
-                    ::$prefix::mem::transmute(self)
+                    ::#prefix::mem::transmute(self)
                 }
 
                 #[inline]
                 pub unsafe fn as_mut(&mut self) -> &mut T {
-                    ::$prefix::mem::transmute(self)
+                    ::#prefix::mem::transmute(self)
                 }
             }
-        ).unwrap();
+        };
 
-        let union_field_default_impl = quote_item!(&ctx.ext_cx(),
-            impl<T> ::$prefix::default::Default for __BindgenUnionField<T> {
+        let union_field_default_impl = quote! {
+            impl<T> ::#prefix::default::Default for __BindgenUnionField<T> {
                 #[inline]
                 fn default() -> Self {
                     Self::new()
                 }
             }
-        ).unwrap();
+        };
 
-        let union_field_clone_impl = quote_item!(&ctx.ext_cx(),
-            impl<T> ::$prefix::clone::Clone for __BindgenUnionField<T> {
+        let union_field_clone_impl = quote! {
+            impl<T> ::#prefix::clone::Clone for __BindgenUnionField<T> {
                 #[inline]
                 fn clone(&self) -> Self {
                     Self::new()
                 }
             }
-        ).unwrap();
+        };
 
-        let union_field_copy_impl = quote_item!(&ctx.ext_cx(),
-            impl<T> ::$prefix::marker::Copy for __BindgenUnionField<T> {}
-        ).unwrap();
+        let union_field_copy_impl = quote! {
+            impl<T> ::#prefix::marker::Copy for __BindgenUnionField<T> {}
+        };
 
-        let union_field_debug_impl = quote_item!(ctx.ext_cx(),
-            impl<T> ::$prefix::fmt::Debug for __BindgenUnionField<T> {
-                fn fmt(&self, fmt: &mut ::$prefix::fmt::Formatter)
-                       -> ::$prefix::fmt::Result {
+        let union_field_debug_impl = quote! {
+            impl<T> ::#prefix::fmt::Debug for __BindgenUnionField<T> {
+                fn fmt(&self, fmt: &mut ::#prefix::fmt::Formatter)
+                       -> ::#prefix::fmt::Result {
                     fmt.write_str("__BindgenUnionField")
                 }
             }
-        ).unwrap();
+        };
 
         // The actual memory of the filed will be hashed, so that's why these
         // field doesn't do anything with the hash.
-        let union_field_hash_impl = quote_item!(&ctx.ext_cx(),
-            impl<T> ::$prefix::hash::Hash for __BindgenUnionField<T> {
-                fn hash<H: ::$prefix::hash::Hasher>(&self, _state: &mut H) {
+        let union_field_hash_impl = quote! {
+            impl<T> ::#prefix::hash::Hash for __BindgenUnionField<T> {
+                fn hash<H: ::#prefix::hash::Hasher>(&self, _state: &mut H) {
                 }
             }
-        ).unwrap();
+        };
 
-        let union_field_partialeq_impl = quote_item!(&ctx.ext_cx(),
-           impl<T> ::$prefix::cmp::PartialEq for __BindgenUnionField<T> {
+        let union_field_partialeq_impl = quote! {
+            impl<T> ::#prefix::cmp::PartialEq for __BindgenUnionField<T> {
                fn eq(&self, _other: &__BindgenUnionField<T>) -> bool {
                    true
                }
            }
-        ).unwrap();
+        };
 
-        let union_field_eq_impl = quote_item!(&ctx.ext_cx(),
-           impl<T> ::$prefix::cmp::Eq for __BindgenUnionField<T> {
+        let union_field_eq_impl = quote! {
+           impl<T> ::#prefix::cmp::Eq for __BindgenUnionField<T> {
            }
-        )
-            .unwrap();
+        };
 
         let items = vec![union_field_decl,
                          union_field_impl,
@@ -3649,67 +3454,67 @@ mod utils {
 
     pub fn prepend_incomplete_array_types(
         ctx: &BindgenContext,
-        result: &mut Vec<P<ast::Item>>,
+        result: &mut Vec<quote::Tokens>,
     ) {
         let prefix = ctx.trait_prefix();
 
-        let incomplete_array_decl = quote_item!(ctx.ext_cx(),
+        let incomplete_array_decl = quote! {
             #[repr(C)]
             #[derive(Default)]
             pub struct __IncompleteArrayField<T>(
-                ::$prefix::marker::PhantomData<T>);
-        ).unwrap();
+                ::#prefix::marker::PhantomData<T>);
+        };
 
-        let incomplete_array_impl = quote_item!(&ctx.ext_cx(),
+        let incomplete_array_impl = quote! {
             impl<T> __IncompleteArrayField<T> {
                 #[inline]
                 pub fn new() -> Self {
-                    __IncompleteArrayField(::$prefix::marker::PhantomData)
+                    __IncompleteArrayField(::#prefix::marker::PhantomData)
                 }
 
                 #[inline]
                 pub unsafe fn as_ptr(&self) -> *const T {
-                    ::$prefix::mem::transmute(self)
+                    ::#prefix::mem::transmute(self)
                 }
 
                 #[inline]
                 pub unsafe fn as_mut_ptr(&mut self) -> *mut T {
-                    ::$prefix::mem::transmute(self)
+                    ::#prefix::mem::transmute(self)
                 }
 
                 #[inline]
                 pub unsafe fn as_slice(&self, len: usize) -> &[T] {
-                    ::$prefix::slice::from_raw_parts(self.as_ptr(), len)
+                    ::#prefix::slice::from_raw_parts(self.as_ptr(), len)
                 }
 
                 #[inline]
                 pub unsafe fn as_mut_slice(&mut self, len: usize) -> &mut [T] {
-                    ::$prefix::slice::from_raw_parts_mut(self.as_mut_ptr(), len)
+                    ::#prefix::slice::from_raw_parts_mut(self.as_mut_ptr(), len)
                 }
             }
-        ).unwrap();
+        };
 
-        let incomplete_array_debug_impl = quote_item!(ctx.ext_cx(),
-            impl<T> ::$prefix::fmt::Debug for __IncompleteArrayField<T> {
-                fn fmt(&self, fmt: &mut ::$prefix::fmt::Formatter)
-                       -> ::$prefix::fmt::Result {
+        let incomplete_array_debug_impl = quote! {
+            impl<T> ::#prefix::fmt::Debug for __IncompleteArrayField<T> {
+                fn fmt(&self, fmt: &mut ::#prefix::fmt::Formatter)
+                       -> ::#prefix::fmt::Result {
                     fmt.write_str("__IncompleteArrayField")
                 }
             }
-        ).unwrap();
+        };
 
-        let incomplete_array_clone_impl = quote_item!(&ctx.ext_cx(),
-            impl<T> ::$prefix::clone::Clone for __IncompleteArrayField<T> {
+        let incomplete_array_clone_impl = quote! {
+            impl<T> ::#prefix::clone::Clone for __IncompleteArrayField<T> {
                 #[inline]
                 fn clone(&self) -> Self {
                     Self::new()
                 }
             }
-        ).unwrap();
+        };
 
-        let incomplete_array_copy_impl = quote_item!(&ctx.ext_cx(),
-            impl<T> ::$prefix::marker::Copy for __IncompleteArrayField<T> {}
-        ).unwrap();
+        let incomplete_array_copy_impl = quote! {
+            impl<T> ::#prefix::marker::Copy for __IncompleteArrayField<T> {}
+        };
 
         let items = vec![incomplete_array_decl,
                          incomplete_array_impl,
@@ -3722,17 +3527,16 @@ mod utils {
     }
 
     pub fn prepend_complex_type(
-        ctx: &BindgenContext,
-        result: &mut Vec<P<ast::Item>>,
+        result: &mut Vec<quote::Tokens>,
     ) {
-        let complex_type = quote_item!(ctx.ext_cx(),
+        let complex_type = quote! {
             #[derive(PartialEq, Copy, Clone, Hash, Debug, Default)]
             #[repr(C)]
             pub struct __BindgenComplex<T> {
                 pub re: T,
                 pub im: T
             }
-        ).unwrap();
+        };
 
         let items = vec![complex_type];
         let old_items = mem::replace(result, items);
@@ -3743,53 +3547,38 @@ mod utils {
         item: &Item,
         ctx: &BindgenContext,
         template_params: Vec<ItemId>,
-    ) -> error::Result<P<ast::Ty>> {
+    ) -> error::Result<quote::Tokens> {
         let path = item.namespace_aware_canonical_path(ctx);
-        let builder = aster::AstBuilder::new().ty().path();
 
         let template_params = template_params
             .iter()
             .map(|param| param.try_to_rust_ty(ctx, &()))
             .collect::<error::Result<Vec<_>>>()?;
 
-        // XXX: I suck at aster.
-        if path.len() == 1 {
-            return Ok(
-                builder
-                    .segment(&path[0])
-                    .with_tys(template_params)
-                    .build()
-                    .build(),
-            );
-        }
+        let mut tokens = quote! {};
+        tokens.append_separated(path.into_iter().map(quote::Ident::new), "::");
 
-        let mut builder = builder.id(&path[0]);
-        for (i, segment) in path.iter().skip(1).enumerate() {
-            // Take into account the skip(1)
-            builder = if i == path.len() - 2 {
-                // XXX Extra clone courtesy of the borrow checker.
-                builder
-                    .segment(&segment)
-                    .with_tys(template_params.clone())
-                    .build()
-            } else {
-                builder.segment(&segment).build()
-            }
+        if template_params.is_empty() {
+            Ok(tokens)
+        } else {
+            Ok(quote! {
+                #tokens < #( #template_params ),* >
+            })
         }
-
-        Ok(builder.build())
     }
 
-    fn primitive_ty(ctx: &BindgenContext, name: &str) -> P<ast::Ty> {
-        let ident = ctx.rust_ident_raw(&name);
-        quote_ty!(ctx.ext_cx(), $ident)
+    fn primitive_ty(ctx: &BindgenContext, name: &str) -> quote::Tokens {
+        let ident = ctx.rust_ident_raw(name);
+        quote! {
+            #ident
+        }
     }
 
     pub fn type_from_named(
         ctx: &BindgenContext,
         name: &str,
         _inner: ItemId,
-    ) -> Option<P<ast::Ty>> {
+    ) -> Option<quote::Tokens> {
         // FIXME: We could use the inner item to check this is really a
         // primitive type but, who the heck overrides these anyway?
         Some(match name {
@@ -3809,42 +3598,27 @@ mod utils {
         })
     }
 
-    pub fn rust_fndecl_from_signature(
-        ctx: &BindgenContext,
-        sig: &Item,
-    ) -> P<ast::FnDecl> {
-        let signature = sig.kind().expect_type().canonical_type(ctx);
-        let signature = match *signature.kind() {
-            TypeKind::Function(ref sig) => sig,
-            _ => panic!("How?"),
-        };
-
-        let decl_ty = signature.try_to_rust_ty(ctx, sig).expect(
-            "function signature to Rust type conversion is infallible",
-        );
-        match decl_ty.unwrap().node {
-            ast::TyKind::BareFn(bare_fn) => bare_fn.unwrap().decl,
-            _ => panic!("How did this happen exactly?"),
-        }
-    }
-
     pub fn fnsig_return_ty(
         ctx: &BindgenContext,
         sig: &FunctionSig,
-    ) -> ast::FunctionRetTy {
+    ) -> quote::Tokens {
         let return_item = ctx.resolve_item(sig.return_type());
         if let TypeKind::Void = *return_item.kind().expect_type().kind() {
-            ast::FunctionRetTy::Default(ctx.span())
+            quote! { }
         } else {
-            ast::FunctionRetTy::Ty(return_item.to_rust_ty_or_opaque(ctx, &()))
+            let ret_ty = return_item.to_rust_ty_or_opaque(ctx, &());
+            quote! {
+                -> #ret_ty
+            }
         }
     }
 
     pub fn fnsig_arguments(
         ctx: &BindgenContext,
         sig: &FunctionSig,
-    ) -> Vec<ast::Arg> {
+    ) -> Vec<quote::Tokens> {
         use super::ToPtr;
+
         let mut unnamed_arguments = 0;
         sig.argument_types().iter().map(|&(ref name, ty)| {
             let arg_item = ctx.resolve_item(ty);
@@ -3861,13 +3635,15 @@ mod utils {
             let arg_ty = match *arg_ty.canonical_type(ctx).kind() {
                 TypeKind::Array(t, _) => {
                     t.to_rust_ty_or_opaque(ctx, &())
-                        .to_ptr(ctx.resolve_type(t).is_const(), ctx.span())
+                        .to_ptr(ctx.resolve_type(t).is_const())
                 },
                 TypeKind::Pointer(inner) => {
                     let inner = ctx.resolve_item(inner);
                     let inner_ty = inner.expect_type();
                     if let TypeKind::ObjCInterface(_) = *inner_ty.canonical_type(ctx).kind() {
-                        quote_ty!(ctx.ext_cx(), id)
+                        quote! {
+                            id
+                        }
                     } else {
                         arg_item.to_rust_ty_or_opaque(ctx, &())
                     }
@@ -3886,12 +3662,11 @@ mod utils {
             };
 
             assert!(!arg_name.is_empty());
+            let arg_name = ctx.rust_ident(arg_name);
 
-            ast::Arg {
-                ty: arg_ty,
-                pat: aster::AstBuilder::new().pat().id(arg_name),
-                id: ast::DUMMY_NODE_ID,
+            quote! {
+                #arg_name : #arg_ty
             }
-        }).collect::<Vec<_>>()
+        }).collect()
     }
 }
diff --git a/src/codegen/struct_layout.rs b/src/codegen/struct_layout.rs
index 956a1f44..06059853 100644
--- a/src/codegen/struct_layout.rs
+++ b/src/codegen/struct_layout.rs
@@ -2,22 +2,19 @@
 
 use super::helpers;
 
-use aster::struct_field::StructFieldBuilder;
-
 use ir::comp::CompInfo;
 use ir::context::BindgenContext;
 use ir::layout::Layout;
 use ir::ty::{Type, TypeKind};
+use quote;
 use std::cmp;
 use std::mem;
 
-use syntax::ast;
-
 /// Trace the layout of struct.
 #[derive(Debug)]
-pub struct StructLayoutTracker<'a, 'ctx: 'a> {
+pub struct StructLayoutTracker<'a> {
     name: &'a str,
-    ctx: &'a BindgenContext<'ctx>,
+    ctx: &'a BindgenContext,
     comp: &'a CompInfo,
     latest_offset: usize,
     padding_count: usize,
@@ -80,9 +77,9 @@ fn test_bytes_from_bits_pow2() {
     }
 }
 
-impl<'a, 'ctx> StructLayoutTracker<'a, 'ctx> {
+impl<'a> StructLayoutTracker<'a> {
     pub fn new(
-        ctx: &'a BindgenContext<'ctx>,
+        ctx: &'a BindgenContext,
         comp: &'a CompInfo,
         name: &'a str,
     ) -> Self {
@@ -154,7 +151,7 @@ impl<'a, 'ctx> StructLayoutTracker<'a, 'ctx> {
         field_name: &str,
         field_ty: &Type,
         field_offset: Option<usize>,
-    ) -> Option<ast::StructField> {
+    ) -> Option<quote::Tokens> {
         let mut field_layout = match field_ty.layout(self.ctx) {
             Some(l) => l,
             None => return None,
@@ -241,7 +238,7 @@ impl<'a, 'ctx> StructLayoutTracker<'a, 'ctx> {
         padding_layout.map(|layout| self.padding_field(layout))
     }
 
-    pub fn pad_struct(&mut self, layout: Layout) -> Option<ast::StructField> {
+    pub fn pad_struct(&mut self, layout: Layout) -> Option<quote::Tokens> {
         debug!(
             "pad_struct:\n\tself = {:#?}\n\tlayout = {:#?}",
             self,
@@ -291,17 +288,15 @@ impl<'a, 'ctx> StructLayoutTracker<'a, 'ctx> {
         }
     }
 
-    pub fn align_struct(&self, layout: Layout) -> Option<ast::StructField> {
+    pub fn align_struct(&self, layout: Layout) -> Option<quote::Tokens> {
         if self.max_field_align < layout.align &&
             layout.align <= mem::size_of::<*mut ()>()
         {
             let ty = helpers::blob(Layout::new(0, layout.align));
 
-            Some(
-                StructFieldBuilder::named("__bindgen_align")
-                    .pub_()
-                    .build_ty(ty),
-            )
+            Some(quote! {
+                pub __bindgen_align: #ty ,
+            })
         } else {
             None
         }
@@ -311,19 +306,19 @@ impl<'a, 'ctx> StructLayoutTracker<'a, 'ctx> {
         align_to(self.latest_offset, layout.align) - self.latest_offset
     }
 
-    fn padding_field(&mut self, layout: Layout) -> ast::StructField {
+    fn padding_field(&mut self, layout: Layout) -> quote::Tokens {
         let ty = helpers::blob(layout);
         let padding_count = self.padding_count;
 
         self.padding_count += 1;
 
-        let padding_field_name = format!("__bindgen_padding_{}", padding_count);
+        let padding_field_name = quote::Ident::new(format!("__bindgen_padding_{}", padding_count));
 
         self.max_field_align = cmp::max(self.max_field_align, layout.align);
 
-        StructFieldBuilder::named(padding_field_name)
-            .pub_()
-            .build_ty(ty)
+        quote! {
+            pub #padding_field_name : #ty ,
+        }
     }
 
     /// Returns whether the new field is known to merge with a bitfield.
diff --git a/src/ir/analysis/derive_copy.rs b/src/ir/analysis/derive_copy.rs
index 1890dcec..ef01c65a 100644
--- a/src/ir/analysis/derive_copy.rs
+++ b/src/ir/analysis/derive_copy.rs
@@ -31,11 +31,8 @@ use std::collections::HashSet;
 ///   derived copy if any of the template arguments or template definition
 ///   cannot derive copy.
 #[derive(Debug, Clone)]
-pub struct CannotDeriveCopy<'ctx, 'gen>
-where
-    'gen: 'ctx,
-{
-    ctx: &'ctx BindgenContext<'gen>,
+pub struct CannotDeriveCopy<'ctx> {
+    ctx: &'ctx BindgenContext,
 
     // The incremental result of this analysis's computation. Everything in this
     // set cannot derive copy.
@@ -51,7 +48,7 @@ where
     dependencies: HashMap<ItemId, Vec<ItemId>>,
 }
 
-impl<'ctx, 'gen> CannotDeriveCopy<'ctx, 'gen> {
+impl<'ctx> CannotDeriveCopy<'ctx> {
     fn consider_edge(kind: EdgeKind) -> bool {
         match kind {
             // These are the only edges that can affect whether a type can derive
@@ -97,12 +94,12 @@ impl<'ctx, 'gen> CannotDeriveCopy<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> MonotoneFramework for CannotDeriveCopy<'ctx, 'gen> {
+impl<'ctx> MonotoneFramework for CannotDeriveCopy<'ctx> {
     type Node = ItemId;
-    type Extra = &'ctx BindgenContext<'gen>;
+    type Extra = &'ctx BindgenContext;
     type Output = HashSet<ItemId>;
 
-    fn new(ctx: &'ctx BindgenContext<'gen>) -> CannotDeriveCopy<'ctx, 'gen> {
+    fn new(ctx: &'ctx BindgenContext) -> CannotDeriveCopy<'ctx> {
         let cannot_derive_copy = HashSet::new();
         let dependencies = generate_dependencies(ctx, Self::consider_edge);
 
@@ -336,8 +333,8 @@ impl<'ctx, 'gen> MonotoneFramework for CannotDeriveCopy<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> From<CannotDeriveCopy<'ctx, 'gen>> for HashSet<ItemId> {
-    fn from(analysis: CannotDeriveCopy<'ctx, 'gen>) -> Self {
+impl<'ctx> From<CannotDeriveCopy<'ctx>> for HashSet<ItemId> {
+    fn from(analysis: CannotDeriveCopy<'ctx>) -> Self {
         analysis.cannot_derive_copy
     }
 }
diff --git a/src/ir/analysis/derive_debug.rs b/src/ir/analysis/derive_debug.rs
index b7a35132..2bfaff71 100644
--- a/src/ir/analysis/derive_debug.rs
+++ b/src/ir/analysis/derive_debug.rs
@@ -33,11 +33,8 @@ use std::collections::HashSet;
 ///   derived debug if any of the template arguments or template definition
 ///   cannot derive debug.
 #[derive(Debug, Clone)]
-pub struct CannotDeriveDebug<'ctx, 'gen>
-where
-    'gen: 'ctx,
-{
-    ctx: &'ctx BindgenContext<'gen>,
+pub struct CannotDeriveDebug<'ctx> {
+    ctx: &'ctx BindgenContext,
 
     // The incremental result of this analysis's computation. Everything in this
     // set cannot derive debug.
@@ -53,7 +50,7 @@ where
     dependencies: HashMap<ItemId, Vec<ItemId>>,
 }
 
-impl<'ctx, 'gen> CannotDeriveDebug<'ctx, 'gen> {
+impl<'ctx> CannotDeriveDebug<'ctx> {
     fn consider_edge(kind: EdgeKind) -> bool {
         match kind {
             // These are the only edges that can affect whether a type can derive
@@ -99,12 +96,12 @@ impl<'ctx, 'gen> CannotDeriveDebug<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> MonotoneFramework for CannotDeriveDebug<'ctx, 'gen> {
+impl<'ctx> MonotoneFramework for CannotDeriveDebug<'ctx> {
     type Node = ItemId;
-    type Extra = &'ctx BindgenContext<'gen>;
+    type Extra = &'ctx BindgenContext;
     type Output = HashSet<ItemId>;
 
-    fn new(ctx: &'ctx BindgenContext<'gen>) -> CannotDeriveDebug<'ctx, 'gen> {
+    fn new(ctx: &'ctx BindgenContext) -> CannotDeriveDebug<'ctx> {
         let cannot_derive_debug = HashSet::new();
         let dependencies = generate_dependencies(ctx, Self::consider_edge);
 
@@ -355,8 +352,8 @@ impl<'ctx, 'gen> MonotoneFramework for CannotDeriveDebug<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> From<CannotDeriveDebug<'ctx, 'gen>> for HashSet<ItemId> {
-    fn from(analysis: CannotDeriveDebug<'ctx, 'gen>) -> Self {
+impl<'ctx> From<CannotDeriveDebug<'ctx>> for HashSet<ItemId> {
+    fn from(analysis: CannotDeriveDebug<'ctx>) -> Self {
         analysis.cannot_derive_debug
     }
 }
diff --git a/src/ir/analysis/derive_default.rs b/src/ir/analysis/derive_default.rs
index 19f4a842..96805863 100644
--- a/src/ir/analysis/derive_default.rs
+++ b/src/ir/analysis/derive_default.rs
@@ -30,11 +30,8 @@ use std::collections::HashSet;
 /// * If T is a compound type, default cannot be derived if any of its base member
 ///   or field cannot be derived default.
 #[derive(Debug, Clone)]
-pub struct CannotDeriveDefault<'ctx, 'gen>
-where
-    'gen: 'ctx,
-{
-    ctx: &'ctx BindgenContext<'gen>,
+pub struct CannotDeriveDefault<'ctx> {
+    ctx: &'ctx BindgenContext,
 
     // The incremental result of this analysis's computation. Everything in this
     // set cannot derive default.
@@ -50,7 +47,7 @@ where
     dependencies: HashMap<ItemId, Vec<ItemId>>,
 }
 
-impl<'ctx, 'gen> CannotDeriveDefault<'ctx, 'gen> {
+impl<'ctx> CannotDeriveDefault<'ctx> {
     fn consider_edge(kind: EdgeKind) -> bool {
         match kind {
             // These are the only edges that can affect whether a type can derive
@@ -94,12 +91,12 @@ impl<'ctx, 'gen> CannotDeriveDefault<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> MonotoneFramework for CannotDeriveDefault<'ctx, 'gen> {
+impl<'ctx> MonotoneFramework for CannotDeriveDefault<'ctx> {
     type Node = ItemId;
-    type Extra = &'ctx BindgenContext<'gen>;
+    type Extra = &'ctx BindgenContext;
     type Output = HashSet<ItemId>;
 
-    fn new(ctx: &'ctx BindgenContext<'gen>) -> CannotDeriveDefault<'ctx, 'gen> {
+    fn new(ctx: &'ctx BindgenContext) -> CannotDeriveDefault<'ctx> {
         let mut dependencies = HashMap::new();
         let cannot_derive_default = HashSet::new();
 
@@ -388,8 +385,8 @@ impl<'ctx, 'gen> MonotoneFramework for CannotDeriveDefault<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> From<CannotDeriveDefault<'ctx, 'gen>> for HashSet<ItemId> {
-    fn from(analysis: CannotDeriveDefault<'ctx, 'gen>) -> Self {
+impl<'ctx> From<CannotDeriveDefault<'ctx>> for HashSet<ItemId> {
+    fn from(analysis: CannotDeriveDefault<'ctx>) -> Self {
         analysis.cannot_derive_default
     }
 }
diff --git a/src/ir/analysis/derive_hash.rs b/src/ir/analysis/derive_hash.rs
index ee9cb23a..80ea0abf 100644
--- a/src/ir/analysis/derive_hash.rs
+++ b/src/ir/analysis/derive_hash.rs
@@ -33,11 +33,8 @@ use std::collections::HashSet;
 ///   derived hash if any of the template arguments or template definition
 ///   cannot derive hash.
 #[derive(Debug, Clone)]
-pub struct CannotDeriveHash<'ctx, 'gen>
-where
-    'gen: 'ctx,
-{
-    ctx: &'ctx BindgenContext<'gen>,
+pub struct CannotDeriveHash<'ctx> {
+    ctx: &'ctx BindgenContext,
 
     // The incremental result of this analysis's computation. Everything in this
     // set cannot derive hash.
@@ -53,7 +50,7 @@ where
     dependencies: HashMap<ItemId, Vec<ItemId>>,
 }
 
-impl<'ctx, 'gen> CannotDeriveHash<'ctx, 'gen> {
+impl<'ctx> CannotDeriveHash<'ctx> {
     fn consider_edge(kind: EdgeKind) -> bool {
         match kind {
             // These are the only edges that can affect whether a type can derive
@@ -92,12 +89,12 @@ impl<'ctx, 'gen> CannotDeriveHash<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> MonotoneFramework for CannotDeriveHash<'ctx, 'gen> {
+impl<'ctx> MonotoneFramework for CannotDeriveHash<'ctx> {
     type Node = ItemId;
-    type Extra = &'ctx BindgenContext<'gen>;
+    type Extra = &'ctx BindgenContext;
     type Output = HashSet<ItemId>;
 
-    fn new(ctx: &'ctx BindgenContext<'gen>) -> CannotDeriveHash<'ctx, 'gen> {
+    fn new(ctx: &'ctx BindgenContext) -> CannotDeriveHash<'ctx> {
         let cannot_derive_hash = HashSet::new();
         let dependencies = generate_dependencies(ctx, Self::consider_edge);
 
@@ -356,8 +353,8 @@ impl<'ctx, 'gen> MonotoneFramework for CannotDeriveHash<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> From<CannotDeriveHash<'ctx, 'gen>> for HashSet<ItemId> {
-    fn from(analysis: CannotDeriveHash<'ctx, 'gen>) -> Self {
+impl<'ctx> From<CannotDeriveHash<'ctx>> for HashSet<ItemId> {
+    fn from(analysis: CannotDeriveHash<'ctx>) -> Self {
         analysis.cannot_derive_hash
     }
 }
diff --git a/src/ir/analysis/derive_partial_eq.rs b/src/ir/analysis/derive_partial_eq.rs
index 45ba67a5..96689601 100644
--- a/src/ir/analysis/derive_partial_eq.rs
+++ b/src/ir/analysis/derive_partial_eq.rs
@@ -33,11 +33,8 @@ use std::collections::HashSet;
 ///   derived partialeq if any of the template arguments or template definition
 ///   cannot derive partialeq.
 #[derive(Debug, Clone)]
-pub struct CannotDerivePartialEq<'ctx, 'gen>
-where
-    'gen: 'ctx,
-{
-    ctx: &'ctx BindgenContext<'gen>,
+pub struct CannotDerivePartialEq<'ctx> {
+    ctx: &'ctx BindgenContext,
 
     // The incremental result of this analysis's computation. Everything in this
     // set cannot derive partialeq.
@@ -53,7 +50,7 @@ where
     dependencies: HashMap<ItemId, Vec<ItemId>>,
 }
 
-impl<'ctx, 'gen> CannotDerivePartialEq<'ctx, 'gen> {
+impl<'ctx> CannotDerivePartialEq<'ctx> {
     fn consider_edge(kind: EdgeKind) -> bool {
         match kind {
             // These are the only edges that can affect whether a type can derive
@@ -92,14 +89,14 @@ impl<'ctx, 'gen> CannotDerivePartialEq<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> MonotoneFramework for CannotDerivePartialEq<'ctx, 'gen> {
+impl<'ctx> MonotoneFramework for CannotDerivePartialEq<'ctx> {
     type Node = ItemId;
-    type Extra = &'ctx BindgenContext<'gen>;
+    type Extra = &'ctx BindgenContext;
     type Output = HashSet<ItemId>;
 
     fn new(
-        ctx: &'ctx BindgenContext<'gen>,
-    ) -> CannotDerivePartialEq<'ctx, 'gen> {
+        ctx: &'ctx BindgenContext,
+    ) -> CannotDerivePartialEq<'ctx> {
         let cannot_derive_partialeq = HashSet::new();
         let dependencies = generate_dependencies(ctx, Self::consider_edge);
 
@@ -365,8 +362,8 @@ impl<'ctx, 'gen> MonotoneFramework for CannotDerivePartialEq<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> From<CannotDerivePartialEq<'ctx, 'gen>> for HashSet<ItemId> {
-    fn from(analysis: CannotDerivePartialEq<'ctx, 'gen>) -> Self {
+impl<'ctx> From<CannotDerivePartialEq<'ctx>> for HashSet<ItemId> {
+    fn from(analysis: CannotDerivePartialEq<'ctx>) -> Self {
         analysis.cannot_derive_partialeq
     }
 }
diff --git a/src/ir/analysis/has_destructor.rs b/src/ir/analysis/has_destructor.rs
index b37dbaaa..f6400d7d 100644
--- a/src/ir/analysis/has_destructor.rs
+++ b/src/ir/analysis/has_destructor.rs
@@ -23,11 +23,8 @@ use std::collections::HashSet;
 /// * If T is the type of a field, that field has a destructor if it's not a bitfield,
 ///   and if T has a destructor.
 #[derive(Debug, Clone)]
-pub struct HasDestructorAnalysis<'ctx, 'gen>
-where
-    'gen: 'ctx,
-{
-    ctx: &'ctx BindgenContext<'gen>,
+pub struct HasDestructorAnalysis<'ctx> {
+    ctx: &'ctx BindgenContext,
 
     // The incremental result of this analysis's computation. Everything in this
     // set definitely has a destructor.
@@ -43,7 +40,7 @@ where
     dependencies: HashMap<ItemId, Vec<ItemId>>,
 }
 
-impl<'ctx, 'gen> HasDestructorAnalysis<'ctx, 'gen> {
+impl<'ctx> HasDestructorAnalysis<'ctx> {
     fn consider_edge(kind: EdgeKind) -> bool {
         match kind {
             // These are the only edges that can affect whether a type has a
@@ -69,12 +66,12 @@ impl<'ctx, 'gen> HasDestructorAnalysis<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> MonotoneFramework for HasDestructorAnalysis<'ctx, 'gen> {
+impl<'ctx> MonotoneFramework for HasDestructorAnalysis<'ctx> {
     type Node = ItemId;
-    type Extra = &'ctx BindgenContext<'gen>;
+    type Extra = &'ctx BindgenContext;
     type Output = HashSet<ItemId>;
 
-    fn new(ctx: &'ctx BindgenContext<'gen>) -> Self {
+    fn new(ctx: &'ctx BindgenContext) -> Self {
         let have_destructor = HashSet::new();
         let dependencies = generate_dependencies(ctx, Self::consider_edge);
 
@@ -172,8 +169,8 @@ impl<'ctx, 'gen> MonotoneFramework for HasDestructorAnalysis<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> From<HasDestructorAnalysis<'ctx, 'gen>> for HashSet<ItemId> {
-    fn from(analysis: HasDestructorAnalysis<'ctx, 'gen>) -> Self {
+impl<'ctx> From<HasDestructorAnalysis<'ctx>> for HashSet<ItemId> {
+    fn from(analysis: HasDestructorAnalysis<'ctx>) -> Self {
         analysis.have_destructor
     }
 }
diff --git a/src/ir/analysis/has_float.rs b/src/ir/analysis/has_float.rs
index 85fe241e..959a411b 100644
--- a/src/ir/analysis/has_float.rs
+++ b/src/ir/analysis/has_float.rs
@@ -23,10 +23,8 @@ use ir::comp::FieldMethods;
 ///   float if any of the template arguments or template definition
 ///   has.
 #[derive(Debug, Clone)]
-pub struct HasFloat<'ctx, 'gen>
-    where 'gen: 'ctx
-{
-    ctx: &'ctx BindgenContext<'gen>,
+pub struct HasFloat<'ctx> {
+    ctx: &'ctx BindgenContext,
 
     // The incremental result of this analysis's computation. Everything in this
     // set has float.
@@ -42,7 +40,7 @@ pub struct HasFloat<'ctx, 'gen>
     dependencies: HashMap<ItemId, Vec<ItemId>>,
 }
 
-impl<'ctx, 'gen> HasFloat<'ctx, 'gen> {
+impl<'ctx> HasFloat<'ctx> {
     fn consider_edge(kind: EdgeKind) -> bool {
         match kind {
             EdgeKind::BaseMember |
@@ -79,12 +77,12 @@ impl<'ctx, 'gen> HasFloat<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> MonotoneFramework for HasFloat<'ctx, 'gen> {
+impl<'ctx> MonotoneFramework for HasFloat<'ctx> {
     type Node = ItemId;
-    type Extra = &'ctx BindgenContext<'gen>;
+    type Extra = &'ctx BindgenContext;
     type Output = HashSet<ItemId>;
 
-    fn new(ctx: &'ctx BindgenContext<'gen>) -> HasFloat<'ctx, 'gen> {
+    fn new(ctx: &'ctx BindgenContext) -> HasFloat<'ctx> {
         let has_float = HashSet::new();
         let dependencies = generate_dependencies(ctx, Self::consider_edge);
 
@@ -232,8 +230,8 @@ impl<'ctx, 'gen> MonotoneFramework for HasFloat<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> From<HasFloat<'ctx, 'gen>> for HashSet<ItemId> {
-    fn from(analysis: HasFloat<'ctx, 'gen>) -> Self {
+impl<'ctx> From<HasFloat<'ctx>> for HashSet<ItemId> {
+    fn from(analysis: HasFloat<'ctx>) -> Self {
         analysis.has_float
     }
 }
diff --git a/src/ir/analysis/has_type_param_in_array.rs b/src/ir/analysis/has_type_param_in_array.rs
index c361e9d9..f21bae14 100644
--- a/src/ir/analysis/has_type_param_in_array.rs
+++ b/src/ir/analysis/has_type_param_in_array.rs
@@ -23,11 +23,8 @@ use std::collections::HashSet;
 ///   type parameter in array if any of the template arguments or template definition
 ///   has.
 #[derive(Debug, Clone)]
-pub struct HasTypeParameterInArray<'ctx, 'gen>
-where
-    'gen: 'ctx,
-{
-    ctx: &'ctx BindgenContext<'gen>,
+pub struct HasTypeParameterInArray<'ctx> {
+    ctx: &'ctx BindgenContext,
 
     // The incremental result of this analysis's computation. Everything in this
     // set has array.
@@ -43,7 +40,7 @@ where
     dependencies: HashMap<ItemId, Vec<ItemId>>,
 }
 
-impl<'ctx, 'gen> HasTypeParameterInArray<'ctx, 'gen> {
+impl<'ctx> HasTypeParameterInArray<'ctx> {
     fn consider_edge(kind: EdgeKind) -> bool {
         match kind {
             // These are the only edges that can affect whether a type has type parameter
@@ -86,14 +83,14 @@ impl<'ctx, 'gen> HasTypeParameterInArray<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> MonotoneFramework for HasTypeParameterInArray<'ctx, 'gen> {
+impl<'ctx> MonotoneFramework for HasTypeParameterInArray<'ctx> {
     type Node = ItemId;
-    type Extra = &'ctx BindgenContext<'gen>;
+    type Extra = &'ctx BindgenContext;
     type Output = HashSet<ItemId>;
 
     fn new(
-        ctx: &'ctx BindgenContext<'gen>,
-    ) -> HasTypeParameterInArray<'ctx, 'gen> {
+        ctx: &'ctx BindgenContext,
+    ) -> HasTypeParameterInArray<'ctx> {
         let has_type_parameter_in_array = HashSet::new();
         let dependencies = generate_dependencies(ctx, Self::consider_edge);
 
@@ -249,8 +246,8 @@ impl<'ctx, 'gen> MonotoneFramework for HasTypeParameterInArray<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> From<HasTypeParameterInArray<'ctx, 'gen>> for HashSet<ItemId> {
-    fn from(analysis: HasTypeParameterInArray<'ctx, 'gen>) -> Self {
+impl<'ctx> From<HasTypeParameterInArray<'ctx>> for HashSet<ItemId> {
+    fn from(analysis: HasTypeParameterInArray<'ctx>) -> Self {
         analysis.has_type_parameter_in_array
     }
 }
diff --git a/src/ir/analysis/has_vtable.rs b/src/ir/analysis/has_vtable.rs
index bb85d0c9..b0d48738 100644
--- a/src/ir/analysis/has_vtable.rs
+++ b/src/ir/analysis/has_vtable.rs
@@ -18,11 +18,8 @@ use std::collections::HashSet;
 /// * If T is an instantiation of an abstract template definition, T has
 ///   vtable if template definition has vtable
 #[derive(Debug, Clone)]
-pub struct HasVtableAnalysis<'ctx, 'gen>
-where
-    'gen: 'ctx,
-{
-    ctx: &'ctx BindgenContext<'gen>,
+pub struct HasVtableAnalysis<'ctx> {
+    ctx: &'ctx BindgenContext,
 
     // The incremental result of this analysis's computation. Everything in this
     // set definitely has a vtable.
@@ -38,7 +35,7 @@ where
     dependencies: HashMap<ItemId, Vec<ItemId>>,
 }
 
-impl<'ctx, 'gen> HasVtableAnalysis<'ctx, 'gen> {
+impl<'ctx> HasVtableAnalysis<'ctx> {
     fn consider_edge(kind: EdgeKind) -> bool {
         match kind {
             // These are the only edges that can affect whether a type has a
@@ -62,12 +59,12 @@ impl<'ctx, 'gen> HasVtableAnalysis<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> MonotoneFramework for HasVtableAnalysis<'ctx, 'gen> {
+impl<'ctx> MonotoneFramework for HasVtableAnalysis<'ctx> {
     type Node = ItemId;
-    type Extra = &'ctx BindgenContext<'gen>;
+    type Extra = &'ctx BindgenContext;
     type Output = HashSet<ItemId>;
 
-    fn new(ctx: &'ctx BindgenContext<'gen>) -> HasVtableAnalysis<'ctx, 'gen> {
+    fn new(ctx: &'ctx BindgenContext) -> HasVtableAnalysis<'ctx> {
         let have_vtable = HashSet::new();
         let dependencies = generate_dependencies(ctx, Self::consider_edge);
 
@@ -147,8 +144,8 @@ impl<'ctx, 'gen> MonotoneFramework for HasVtableAnalysis<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> From<HasVtableAnalysis<'ctx, 'gen>> for HashSet<ItemId> {
-    fn from(analysis: HasVtableAnalysis<'ctx, 'gen>) -> Self {
+impl<'ctx> From<HasVtableAnalysis<'ctx>> for HashSet<ItemId> {
+    fn from(analysis: HasVtableAnalysis<'ctx>) -> Self {
         analysis.have_vtable
     }
 }
diff --git a/src/ir/analysis/template_params.rs b/src/ir/analysis/template_params.rs
index caaa8f30..7699a0c2 100644
--- a/src/ir/analysis/template_params.rs
+++ b/src/ir/analysis/template_params.rs
@@ -146,11 +146,8 @@ use std::collections::{HashMap, HashSet};
 /// specially; see `constrain_instantiation_of_blacklisted_template` and its
 /// documentation for details.
 #[derive(Debug, Clone)]
-pub struct UsedTemplateParameters<'ctx, 'gen>
-where
-    'gen: 'ctx,
-{
-    ctx: &'ctx BindgenContext<'gen>,
+pub struct UsedTemplateParameters<'ctx> {
+    ctx: &'ctx BindgenContext,
 
     // The Option is only there for temporary moves out of the hash map. See the
     // comments in `UsedTemplateParameters::constrain` below.
@@ -164,7 +161,7 @@ where
     whitelisted_items: HashSet<ItemId>,
 }
 
-impl<'ctx, 'gen> UsedTemplateParameters<'ctx, 'gen> {
+impl<'ctx> UsedTemplateParameters<'ctx> {
     fn consider_edge(kind: EdgeKind) -> bool {
         match kind {
             // For each of these kinds of edges, if the referent uses a template
@@ -367,14 +364,14 @@ impl<'ctx, 'gen> UsedTemplateParameters<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> MonotoneFramework for UsedTemplateParameters<'ctx, 'gen> {
+impl<'ctx> MonotoneFramework for UsedTemplateParameters<'ctx> {
     type Node = ItemId;
-    type Extra = &'ctx BindgenContext<'gen>;
+    type Extra = &'ctx BindgenContext;
     type Output = HashMap<ItemId, ItemSet>;
 
     fn new(
-        ctx: &'ctx BindgenContext<'gen>,
-    ) -> UsedTemplateParameters<'ctx, 'gen> {
+        ctx: &'ctx BindgenContext,
+    ) -> UsedTemplateParameters<'ctx> {
         let mut used = HashMap::new();
         let mut dependencies = HashMap::new();
         let whitelisted_items: HashSet<_> =
@@ -578,9 +575,9 @@ impl<'ctx, 'gen> MonotoneFramework for UsedTemplateParameters<'ctx, 'gen> {
     }
 }
 
-impl<'ctx, 'gen> From<UsedTemplateParameters<'ctx, 'gen>>
+impl<'ctx> From<UsedTemplateParameters<'ctx>>
     for HashMap<ItemId, ItemSet> {
-    fn from(used_templ_params: UsedTemplateParameters<'ctx, 'gen>) -> Self {
+    fn from(used_templ_params: UsedTemplateParameters<'ctx>) -> Self {
         used_templ_params
             .used
             .into_iter()
diff --git a/src/ir/context.rs b/src/ir/context.rs
index cfbb3766..af1e95e9 100644
--- a/src/ir/context.rs
+++ b/src/ir/context.rs
@@ -22,16 +22,13 @@ use cexpr;
 use clang::{self, Cursor};
 use clang_sys;
 use parse::ClangItemParser;
+use quote;
 use std::borrow::Cow;
 use std::cell::Cell;
 use std::collections::{HashMap, HashSet, hash_map};
 use std::collections::btree_map::{self, BTreeMap};
-use std::fmt;
 use std::iter::IntoIterator;
 use std::mem;
-use syntax::ast::Ident;
-use syntax::codemap::{DUMMY_SP, Span};
-use syntax::ext::base::ExtCtxt;
 
 /// A single identifier for an item.
 ///
@@ -98,19 +95,9 @@ enum TypeKey {
     Declaration(Cursor),
 }
 
-// This is just convenience to avoid creating a manual debug impl for the
-// context.
-struct GenContext<'ctx>(ExtCtxt<'ctx>);
-
-impl<'ctx> fmt::Debug for GenContext<'ctx> {
-    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
-        write!(fmt, "GenContext {{ ... }}")
-    }
-}
-
 /// A context used during parsing and generation of structs.
 #[derive(Debug)]
-pub struct BindgenContext<'ctx> {
+pub struct BindgenContext {
     /// The map of all the items parsed so far.
     ///
     /// It's a BTreeMap because we want the keys to be sorted to have consistent
@@ -168,9 +155,7 @@ pub struct BindgenContext<'ctx> {
 
     collected_typerefs: bool,
 
-    /// Dummy structures for code generation.
-    gen_ctx: Option<&'ctx GenContext<'ctx>>,
-    span: Span,
+    in_codegen: bool,
 
     /// The clang index for parsing.
     index: clang::Index,
@@ -268,24 +253,17 @@ pub struct BindgenContext<'ctx> {
 }
 
 /// A traversal of whitelisted items.
-struct WhitelistedItemsTraversal<'ctx, 'gen>
-where
-    'gen: 'ctx,
-{
-    ctx: &'ctx BindgenContext<'gen>,
+struct WhitelistedItemsTraversal<'ctx> {
+    ctx: &'ctx BindgenContext,
     traversal: ItemTraversal<
         'ctx,
-        'gen,
         ItemSet,
         Vec<ItemId>,
         for<'a> fn(&'a BindgenContext, Edge) -> bool,
     >,
 }
 
-impl<'ctx, 'gen> Iterator for WhitelistedItemsTraversal<'ctx, 'gen>
-where
-    'gen: 'ctx,
-{
+impl<'ctx> Iterator for WhitelistedItemsTraversal<'ctx> {
     type Item = ItemId;
 
     fn next(&mut self) -> Option<ItemId> {
@@ -301,13 +279,10 @@ where
     }
 }
 
-impl<'ctx, 'gen> WhitelistedItemsTraversal<'ctx, 'gen>
-where
-    'gen: 'ctx,
-{
+impl<'ctx> WhitelistedItemsTraversal<'ctx> {
     /// Construct a new whitelisted items traversal.
     pub fn new<R>(
-        ctx: &'ctx BindgenContext<'gen>,
+        ctx: &'ctx BindgenContext,
         roots: R,
         predicate: for<'a> fn(&'a BindgenContext, Edge) -> bool,
     ) -> Self
@@ -344,7 +319,7 @@ fn find_effective_target(clang_args: &[String]) -> (String, bool) {
     (HOST_TARGET.to_owned(), false)
 }
 
-impl<'ctx> BindgenContext<'ctx> {
+impl BindgenContext {
     /// Construct the context for the given `options`.
     pub fn new(options: BindgenOptions) -> Self {
         use clang_sys;
@@ -402,8 +377,7 @@ impl<'ctx> BindgenContext<'ctx> {
             parsed_macros: Default::default(),
             replacements: Default::default(),
             collected_typerefs: false,
-            gen_ctx: None,
-            span: DUMMY_SP,
+            in_codegen: false,
             index: index,
             translation_unit: translation_unit,
             options: options,
@@ -632,24 +606,67 @@ impl<'ctx> BindgenContext<'ctx> {
 
     // TODO: Move all this syntax crap to other part of the code.
 
-    /// Given that we are in the codegen phase, get the syntex context.
-    pub fn ext_cx(&self) -> &ExtCtxt<'ctx> {
-        &self.gen_ctx.expect("Not in gen phase").0
-    }
-
-    /// Given that we are in the codegen phase, get the current syntex span.
-    pub fn span(&self) -> Span {
-        self.span
-    }
-
     /// Mangles a name so it doesn't conflict with any keyword.
     pub fn rust_mangle<'a>(&self, name: &'a str) -> Cow<'a, str> {
-        use syntax::parse::token;
-        let ident = self.rust_ident_raw(name);
-        let token = token::Ident(ident);
-        if token.is_any_keyword() || name.contains("@") ||
-            name.contains("?") || name.contains("$") ||
-            "bool" == name
+        if name.contains("@") ||
+            name.contains("?") ||
+            name.contains("$") ||
+            match name {
+                "abstract" |
+ 	            "alignof" |
+ 	            "as" |
+ 	            "become" |
+ 	            "box" |
+                "break" |
+ 	            "const" |
+ 	            "continue" |
+ 	            "crate" |
+ 	            "do" |
+                "else" |
+ 	            "enum" |
+ 	            "extern" |
+ 	            "false" |
+ 	            "final" |
+                "fn" |
+ 	            "for" |
+ 	            "if" |
+ 	            "impl" |
+ 	            "in" |
+                "let" |
+ 	            "loop" |
+ 	            "macro" |
+ 	            "match" |
+ 	            "mod" |
+                "move" |
+ 	            "mut" |
+ 	            "offsetof" |
+ 	            "override" |
+ 	            "priv" |
+                "proc" |
+ 	            "pub" |
+ 	            "pure" |
+ 	            "ref" |
+ 	            "return" |
+                "Self" |
+ 	            "self" |
+ 	            "sizeof" |
+ 	            "static" |
+ 	            "struct" |
+                "super" |
+ 	            "trait" |
+ 	            "true" |
+ 	            "type" |
+ 	            "typeof" |
+                "unsafe" |
+ 	            "unsized" |
+ 	            "use" |
+ 	            "virtual" |
+ 	            "where" |
+                "while" |
+ 	            "yield" |
+                "bool" => true,
+                _ => false,
+            }
         {
             let mut s = name.to_owned();
             s = s.replace("@", "_");
@@ -662,13 +679,19 @@ impl<'ctx> BindgenContext<'ctx> {
     }
 
     /// Returns a mangled name as a rust identifier.
-    pub fn rust_ident(&self, name: &str) -> Ident {
-        self.rust_ident_raw(&self.rust_mangle(name))
+    pub fn rust_ident<S>(&self, name: S) -> quote::Ident
+    where
+        S: AsRef<str>
+    {
+        self.rust_ident_raw(self.rust_mangle(name.as_ref()))
     }
 
     /// Returns a mangled name as a rust identifier.
-    pub fn rust_ident_raw(&self, name: &str) -> Ident {
-        self.ext_cx().ident_of(name)
+    pub fn rust_ident_raw<T>(&self, name: T) -> quote::Ident
+    where
+        T: Into<quote::Ident>
+    {
+        name.into()
     }
 
     /// Iterate over all items that have been defined.
@@ -891,30 +914,7 @@ impl<'ctx> BindgenContext<'ctx> {
     where
         F: FnOnce(&Self) -> Out,
     {
-        use aster::symbol::ToSymbol;
-        use syntax::ext::expand::ExpansionConfig;
-        use syntax::codemap::{ExpnInfo, MacroBang, NameAndSpan};
-        use syntax::ext::base;
-        use syntax::parse;
-
-        let cfg = ExpansionConfig::default("xxx".to_owned());
-        let sess = parse::ParseSess::new();
-        let mut loader = base::DummyResolver;
-        let mut ctx = GenContext(base::ExtCtxt::new(&sess, cfg, &mut loader));
-
-        ctx.0.bt_push(ExpnInfo {
-            call_site: self.span,
-            callee: NameAndSpan {
-                format: MacroBang("".to_symbol()),
-                allow_internal_unstable: false,
-                span: None,
-            },
-        });
-
-        // FIXME: This is evil, we should move code generation to use a wrapper
-        // of BindgenContext instead, I guess. Even though we know it's fine
-        // because we remove it before the end of this function.
-        self.gen_ctx = Some(unsafe { mem::transmute(&ctx) });
+        self.in_codegen = true;
 
         self.assert_no_dangling_references();
 
@@ -950,7 +950,7 @@ impl<'ctx> BindgenContext<'ctx> {
         self.compute_cannot_derive_partialeq_or_eq();
 
         let ret = cb(self);
-        self.gen_ctx = None;
+        self.in_codegen = false;
         ret
     }
 
@@ -965,9 +965,9 @@ impl<'ctx> BindgenContext<'ctx> {
         }
     }
 
-    fn assert_no_dangling_item_traversal<'me>(
-        &'me self,
-    ) -> traversal::AssertNoDanglingItemsTraversal<'me, 'ctx> {
+    fn assert_no_dangling_item_traversal(
+        &self,
+    ) -> traversal::AssertNoDanglingItemsTraversal {
         assert!(self.in_codegen_phase());
         assert!(self.current_module == self.root_module);
 
@@ -1735,7 +1735,7 @@ impl<'ctx> BindgenContext<'ctx> {
 
     /// Are we in the codegen phase?
     pub fn in_codegen_phase(&self) -> bool {
-        self.gen_ctx.is_some()
+        self.in_codegen
     }
 
     /// Mark the type with the given `name` as replaced by the type with id
@@ -2031,7 +2031,7 @@ impl<'ctx> BindgenContext<'ctx> {
 
     /// Convenient method for getting the prefix to use for most traits in
     /// codegen depending on the `use_core` option.
-    pub fn trait_prefix(&self) -> Ident {
+    pub fn trait_prefix(&self) -> quote::Ident {
         if self.options().use_core {
             self.rust_ident_raw("core")
         } else {
@@ -2244,7 +2244,7 @@ impl ItemResolver {
     }
 
     /// Finish configuring and perform the actual item resolution.
-    pub fn resolve<'a, 'b>(self, ctx: &'a BindgenContext<'b>) -> &'a Item {
+    pub fn resolve(self, ctx: &BindgenContext) -> &Item {
         assert!(ctx.collected_typerefs());
 
         let mut id = self.id;
diff --git a/src/ir/function.rs b/src/ir/function.rs
index 3cf48db7..b08824af 100644
--- a/src/ir/function.rs
+++ b/src/ir/function.rs
@@ -11,8 +11,8 @@ use clang_sys::{self, CXCallingConv};
 use ir::derive::{CanTriviallyDeriveDebug, CanTriviallyDeriveHash,
                  CanTriviallyDerivePartialEq};
 use parse::{ClangItemParser, ClangSubItemParser, ParseError, ParseResult};
+use quote;
 use std::io;
-use syntax::abi;
 
 const RUST_DERIVE_FUNPTR_LIMIT: usize = 12;
 
@@ -136,8 +136,16 @@ impl DotAttributes for Function {
 /// An ABI extracted from a clang cursor.
 #[derive(Debug, Copy, Clone)]
 pub enum Abi {
-    /// A known ABI, that rust also understand.
-    Known(abi::Abi),
+    /// The default C ABI.
+    C,
+    /// The "stdcall" ABI.
+    Stdcall,
+    /// The "fastcall" ABI.
+    Fastcall,
+    /// The "aapcs" ABI.
+    Aapcs,
+    /// The "win64" ABI.
+    Win64,
     /// An unknown or invalid ABI.
     Unknown(CXCallingConv),
 }
@@ -152,6 +160,22 @@ impl Abi {
     }
 }
 
+impl quote::ToTokens for Abi {
+    fn to_tokens(&self, tokens: &mut quote::Tokens) {
+        tokens.append(match *self {
+            Abi::C => quote! { "C" },
+            Abi::Stdcall => quote! { "stdcall" },
+            Abi::Fastcall => quote! { "fastcall" },
+            Abi::Aapcs => quote! { "aapcs" },
+            Abi::Win64 => quote! { "win64" },
+            Abi::Unknown(cc) => panic!(
+                "Cannot turn unknown calling convention to tokens: {:?}",
+                cc
+            ),
+        });
+    }
+}
+
 /// A function signature.
 #[derive(Debug)]
 pub struct FunctionSig {
@@ -171,15 +195,15 @@ pub struct FunctionSig {
 
 fn get_abi(cc: CXCallingConv) -> Abi {
     use clang_sys::*;
-    Abi::Known(match cc {
-        CXCallingConv_Default => abi::Abi::C,
-        CXCallingConv_C => abi::Abi::C,
-        CXCallingConv_X86StdCall => abi::Abi::Stdcall,
-        CXCallingConv_X86FastCall => abi::Abi::Fastcall,
-        CXCallingConv_AAPCS => abi::Abi::Aapcs,
-        CXCallingConv_X86_64Win64 => abi::Abi::Win64,
-        other => return Abi::Unknown(other),
-    })
+    match cc {
+        CXCallingConv_Default => Abi::C,
+        CXCallingConv_C => Abi::C,
+        CXCallingConv_X86StdCall => Abi::Stdcall,
+        CXCallingConv_X86FastCall => Abi::Fastcall,
+        CXCallingConv_AAPCS => Abi::Aapcs,
+        CXCallingConv_X86_64Win64 => Abi::Win64,
+        other => Abi::Unknown(other),
+    }
 }
 
 fn mangling_hack_if_needed(ctx: &BindgenContext, symbol: &mut String) {
@@ -513,8 +537,7 @@ impl CanTriviallyDeriveDebug for FunctionSig {
         }
 
         match self.abi {
-            Abi::Known(abi::Abi::C) |
-            Abi::Unknown(..) => true,
+            Abi::C | Abi::Unknown(..) => true,
             _ => false,
         }
     }
@@ -527,8 +550,7 @@ impl CanTriviallyDeriveHash for FunctionSig {
         }
 
         match self.abi {
-            Abi::Known(abi::Abi::C) |
-            Abi::Unknown(..) => true,
+            Abi::C | Abi::Unknown(..) => true,
             _ => false,
         }
     }
@@ -541,8 +563,7 @@ impl CanTriviallyDerivePartialEq for FunctionSig {
         }
 
         match self.abi {
-            Abi::Known(abi::Abi::C) |
-            Abi::Unknown(..) => true,
+            Abi::C | Abi::Unknown(..) => true,
             _ => false,
         }
     }
diff --git a/src/ir/item.rs b/src/ir/item.rs
index 0dac1287..241bd9ef 100644
--- a/src/ir/item.rs
+++ b/src/ir/item.rs
@@ -93,10 +93,10 @@ pub trait HasFloat {
 /// up to (but not including) the implicit root module.
 pub trait ItemAncestors {
     /// Get an iterable over this item's ancestors.
-    fn ancestors<'a, 'b>(
+    fn ancestors<'a>(
         &self,
-        ctx: &'a BindgenContext<'b>,
-    ) -> ItemAncestorsIter<'a, 'b>;
+        ctx: &'a BindgenContext,
+    ) -> ItemAncestorsIter<'a>;
 }
 
 cfg_if! {
@@ -120,20 +120,14 @@ cfg_if! {
 }
 
 /// An iterator over an item and its ancestors.
-pub struct ItemAncestorsIter<'a, 'b>
-where
-    'b: 'a,
-{
+pub struct ItemAncestorsIter<'a> {
     item: ItemId,
-    ctx: &'a BindgenContext<'b>,
+    ctx: &'a BindgenContext,
     seen: DebugOnlyItemSet,
 }
 
-impl<'a, 'b> ItemAncestorsIter<'a, 'b>
-where
-    'b: 'a,
-{
-    fn new(ctx: &'a BindgenContext<'b>, item: ItemId) -> Self {
+impl<'a> ItemAncestorsIter<'a> {
+    fn new(ctx: &'a BindgenContext, item: ItemId) -> Self {
         ItemAncestorsIter {
             item: item,
             ctx: ctx,
@@ -142,10 +136,7 @@ where
     }
 }
 
-impl<'a, 'b> Iterator for ItemAncestorsIter<'a, 'b>
-where
-    'b: 'a,
-{
+impl<'a> Iterator for ItemAncestorsIter<'a> {
     type Item = ItemId;
 
     fn next(&mut self) -> Option<Self::Item> {
@@ -238,19 +229,19 @@ impl ItemCanonicalPath for ItemId {
 }
 
 impl ItemAncestors for ItemId {
-    fn ancestors<'a, 'b>(
+    fn ancestors<'a>(
         &self,
-        ctx: &'a BindgenContext<'b>,
-    ) -> ItemAncestorsIter<'a, 'b> {
+        ctx: &'a BindgenContext,
+    ) -> ItemAncestorsIter<'a> {
         ItemAncestorsIter::new(ctx, *self)
     }
 }
 
 impl ItemAncestors for Item {
-    fn ancestors<'a, 'b>(
+    fn ancestors<'a>(
         &self,
-        ctx: &'a BindgenContext<'b>,
-    ) -> ItemAncestorsIter<'a, 'b> {
+        ctx: &'a BindgenContext,
+    ) -> ItemAncestorsIter<'a> {
         self.id().ancestors(ctx)
     }
 }
@@ -638,10 +629,10 @@ impl Item {
     }
 
     /// Take out item NameOptions
-    pub fn name<'item, 'ctx>(
-        &'item self,
-        ctx: &'item BindgenContext<'ctx>,
-    ) -> NameOptions<'item, 'ctx> {
+    pub fn name<'a>(
+        &'a self,
+        ctx: &'a BindgenContext,
+    ) -> NameOptions<'a> {
         NameOptions::new(self, ctx)
     }
 
@@ -1773,18 +1764,15 @@ impl ItemCanonicalPath for Item {
 /// Builder struct for naming variations, which hold inside different
 /// flags for naming options.
 #[derive(Debug)]
-pub struct NameOptions<'item, 'ctx>
-where
-    'ctx: 'item,
-{
-    item: &'item Item,
-    ctx: &'item BindgenContext<'ctx>,
+pub struct NameOptions<'a> {
+    item: &'a Item,
+    ctx: &'a BindgenContext,
     within_namespaces: bool,
 }
 
-impl<'item, 'ctx> NameOptions<'item, 'ctx> {
+impl<'a> NameOptions<'a> {
     /// Construct a new `NameOptions`
-    pub fn new(item: &'item Item, ctx: &'item BindgenContext<'ctx>) -> Self {
+    pub fn new(item: &'a Item, ctx: &'a BindgenContext) -> Self {
         NameOptions {
             item: item,
             ctx: ctx,
diff --git a/src/ir/objc.rs b/src/ir/objc.rs
index 843dd722..cabbd389 100644
--- a/src/ir/objc.rs
+++ b/src/ir/objc.rs
@@ -12,6 +12,7 @@ use clang_sys::CXCursor_ObjCClassRef;
 use clang_sys::CXCursor_ObjCInstanceMethodDecl;
 use clang_sys::CXCursor_ObjCProtocolDecl;
 use clang_sys::CXCursor_ObjCProtocolRef;
+use quote;
 
 /// Objective C interface as used in TypeKind
 ///
@@ -211,13 +212,19 @@ impl ObjCMethod {
     }
 
     /// Formats the method call
-    pub fn format_method_call(&self, args: &[String]) -> String {
-        let split_name: Vec<&str> =
-            self.name.split(':').filter(|p| !p.is_empty()).collect();
+    pub fn format_method_call(&self, args: &[quote::Tokens]) -> quote::Tokens {
+        let split_name: Vec<_> = self.name
+            .split(':')
+            .filter(|p| !p.is_empty())
+            .map(quote::Ident::new)
+            .collect();
 
         // No arguments
         if args.len() == 0 && split_name.len() == 1 {
-            return split_name[0].to_string();
+            let name = &split_name[0];
+            return quote! {
+                #name
+            };
         }
 
         // Check right amount of arguments
@@ -229,12 +236,14 @@ impl ObjCMethod {
             );
         }
 
-        split_name
-            .iter()
+        let args = split_name
+            .into_iter()
             .zip(args.iter())
-            .map(|parts| format!("{}:{} ", parts.0, parts.1))
-            .collect::<Vec<_>>()
-            .join("")
+            .map(|(arg, ty)| quote! { #arg : #ty });
+
+        quote! {
+            #( #args ),*
+        }
     }
 }
 
diff --git a/src/ir/traversal.rs b/src/ir/traversal.rs
index e4ce946d..f55acc10 100644
--- a/src/ir/traversal.rs
+++ b/src/ir/traversal.rs
@@ -241,9 +241,9 @@ pub fn codegen_edges(ctx: &BindgenContext, edge: Edge) -> bool {
 /// The storage for the set of items that have been seen (although their
 /// outgoing edges might not have been fully traversed yet) in an active
 /// traversal.
-pub trait TraversalStorage<'ctx, 'gen> {
+pub trait TraversalStorage<'ctx> {
     /// Construct a new instance of this TraversalStorage, for a new traversal.
-    fn new(ctx: &'ctx BindgenContext<'gen>) -> Self;
+    fn new(ctx: &'ctx BindgenContext) -> Self;
 
     /// Add the given item to the storage. If the item has never been seen
     /// before, return `true`. Otherwise, return `false`.
@@ -253,8 +253,8 @@ pub trait TraversalStorage<'ctx, 'gen> {
     fn add(&mut self, from: Option<ItemId>, item: ItemId) -> bool;
 }
 
-impl<'ctx, 'gen> TraversalStorage<'ctx, 'gen> for ItemSet {
-    fn new(_: &'ctx BindgenContext<'gen>) -> Self {
+impl<'ctx> TraversalStorage<'ctx> for ItemSet {
+    fn new(_: &'ctx BindgenContext) -> Self {
         ItemSet::new()
     }
 
@@ -267,18 +267,13 @@ impl<'ctx, 'gen> TraversalStorage<'ctx, 'gen> for ItemSet {
 /// each item. This is useful for providing debug assertions with meaningful
 /// diagnostic messages about dangling items.
 #[derive(Debug)]
-pub struct Paths<'ctx, 'gen>(
+pub struct Paths<'ctx>(
     BTreeMap<ItemId, ItemId>,
-    &'ctx BindgenContext<'gen>
-)
-where
-    'gen: 'ctx;
+    &'ctx BindgenContext
+);
 
-impl<'ctx, 'gen> TraversalStorage<'ctx, 'gen> for Paths<'ctx, 'gen>
-where
-    'gen: 'ctx,
-{
-    fn new(ctx: &'ctx BindgenContext<'gen>) -> Self {
+impl<'ctx> TraversalStorage<'ctx> for Paths<'ctx> {
+    fn new(ctx: &'ctx BindgenContext) -> Self {
         Paths(BTreeMap::new(), ctx)
     }
 
@@ -388,14 +383,13 @@ pub trait Trace {
 /// An graph traversal of the transitive closure of references between items.
 ///
 /// See `BindgenContext::whitelisted_items` for more information.
-pub struct ItemTraversal<'ctx, 'gen, Storage, Queue, Predicate>
+pub struct ItemTraversal<'ctx, Storage, Queue, Predicate>
 where
-    'gen: 'ctx,
-    Storage: TraversalStorage<'ctx, 'gen>,
+    Storage: TraversalStorage<'ctx>,
     Queue: TraversalQueue,
     Predicate: TraversalPredicate,
 {
-    ctx: &'ctx BindgenContext<'gen>,
+    ctx: &'ctx BindgenContext,
 
     /// The set of items we have seen thus far in this traversal.
     seen: Storage,
@@ -410,20 +404,19 @@ where
     currently_traversing: Option<ItemId>,
 }
 
-impl<'ctx, 'gen, Storage, Queue, Predicate>
-    ItemTraversal<'ctx, 'gen, Storage, Queue, Predicate>
+impl<'ctx, Storage, Queue, Predicate>
+    ItemTraversal<'ctx, Storage, Queue, Predicate>
 where
-    'gen: 'ctx,
-    Storage: TraversalStorage<'ctx, 'gen>,
+    Storage: TraversalStorage<'ctx>,
     Queue: TraversalQueue,
     Predicate: TraversalPredicate,
 {
     /// Begin a new traversal, starting from the given roots.
     pub fn new<R>(
-        ctx: &'ctx BindgenContext<'gen>,
+        ctx: &'ctx BindgenContext,
         roots: R,
         predicate: Predicate,
-    ) -> ItemTraversal<'ctx, 'gen, Storage, Queue, Predicate>
+    ) -> ItemTraversal<'ctx, Storage, Queue, Predicate>
     where
         R: IntoIterator<Item = ItemId>,
     {
@@ -445,11 +438,10 @@ where
     }
 }
 
-impl<'ctx, 'gen, Storage, Queue, Predicate> Tracer
-    for ItemTraversal<'ctx, 'gen, Storage, Queue, Predicate>
+impl<'ctx, Storage, Queue, Predicate> Tracer
+    for ItemTraversal<'ctx, Storage, Queue, Predicate>
 where
-    'gen: 'ctx,
-    Storage: TraversalStorage<'ctx, 'gen>,
+    Storage: TraversalStorage<'ctx>,
     Queue: TraversalQueue,
     Predicate: TraversalPredicate,
 {
@@ -467,11 +459,10 @@ where
     }
 }
 
-impl<'ctx, 'gen, Storage, Queue, Predicate> Iterator
-    for ItemTraversal<'ctx, 'gen, Storage, Queue, Predicate>
+impl<'ctx, Storage, Queue, Predicate> Iterator
+    for ItemTraversal<'ctx, Storage, Queue, Predicate>
 where
-    'gen: 'ctx,
-    Storage: TraversalStorage<'ctx, 'gen>,
+    Storage: TraversalStorage<'ctx>,
     Queue: TraversalQueue,
     Predicate: TraversalPredicate,
 {
@@ -505,11 +496,10 @@ where
 ///
 /// See `BindgenContext::assert_no_dangling_item_traversal` for more
 /// information.
-pub type AssertNoDanglingItemsTraversal<'ctx, 'gen> =
+pub type AssertNoDanglingItemsTraversal<'ctx> =
     ItemTraversal<
         'ctx,
-        'gen,
-        Paths<'ctx, 'gen>,
+        Paths<'ctx>,
         VecDeque<ItemId>,
         for<'a> fn(&'a BindgenContext, Edge) -> bool,
     >;
diff --git a/src/ir/ty.rs b/src/ir/ty.rs
index b588dbb4..8cfbde10 100644
--- a/src/ir/ty.rs
+++ b/src/ir/ty.rs
@@ -443,6 +443,8 @@ impl DotAttributes for TypeKind {
     where
         W: io::Write,
     {
+        writeln!(out, "<tr><td>type kind</td><td>{}</td></tr>", self.kind_name())?;
+
         if let TypeKind::Comp(ref comp) = *self {
             comp.dot_attributes(ctx, out)?;
         }
@@ -451,6 +453,35 @@ impl DotAttributes for TypeKind {
     }
 }
 
+impl TypeKind {
+    fn kind_name(&self) -> &'static str {
+        match *self {
+            TypeKind::Void => "Void",
+            TypeKind::NullPtr => "NullPtr",
+            TypeKind::Comp(..) => "Comp",
+            TypeKind::Opaque => "Opaque",
+            TypeKind::Int(..) => "Int",
+            TypeKind::Float(..) => "Float",
+            TypeKind::Complex(..) => "Complex",
+            TypeKind::Alias(..) => "Alias",
+            TypeKind::TemplateAlias(..) => "TemplateAlias",
+            TypeKind::Array(..) => "Array",
+            TypeKind::Function(..) => "Function",
+            TypeKind::Enum(..) => "Enum",
+            TypeKind::Pointer(..) => "Pointer",
+            TypeKind::BlockPointer => "BlockPointer",
+            TypeKind::Reference(..) => "Reference",
+            TypeKind::TemplateInstantiation(..) => "TemplateInstantiation",
+            TypeKind::UnresolvedTypeRef(..) => "UnresolvedTypeRef",
+            TypeKind::ResolvedTypeRef(..) => "ResolvedTypeRef",
+            TypeKind::TypeParam => "TypeParam",
+            TypeKind::ObjCInterface(..) => "ObjCInterface",
+            TypeKind::ObjCId => "ObjCId",
+            TypeKind::ObjCSel => "ObjCSel",
+        }
+    }
+}
+
 #[test]
 fn is_invalid_type_param_valid() {
     let ty = Type::new(Some("foo".into()), None, TypeKind::TypeParam, false);
diff --git a/src/lib.rs b/src/lib.rs
index 91b7d8d4..ed63724a 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -13,19 +13,20 @@
 // To avoid rather annoying warnings when matching with CXCursor_xxx as a
 // constant.
 #![allow(non_upper_case_globals)]
+// `quote!` nests quite deeply.
+#![recursion_limit="128"]
 
+extern crate cexpr;
 #[macro_use]
 #[allow(unused_extern_crates)]
 extern crate cfg_if;
-extern crate cexpr;
-extern crate syntex_syntax as syntax;
-extern crate aster;
-extern crate quasi;
 extern crate clang_sys;
-extern crate peeking_take_while;
-extern crate regex;
 #[macro_use]
 extern crate lazy_static;
+extern crate peeking_take_while;
+#[macro_use]
+extern crate quote;
+extern crate regex;
 extern crate which;
 
 #[cfg(feature = "logging")]
@@ -60,6 +61,7 @@ macro_rules! doc_mod {
 }
 
 mod clang;
+mod codegen;
 mod features;
 mod ir;
 mod parse;
@@ -68,19 +70,12 @@ mod time;
 
 pub mod callbacks;
 
-#[cfg(rustfmt)]
-mod codegen;
-
 doc_mod!(clang, clang_docs);
 doc_mod!(features, features_docs);
 doc_mod!(ir, ir_docs);
 doc_mod!(parse, parse_docs);
 doc_mod!(regex_set, regex_set_docs);
 
-mod codegen {
-    include!(concat!(env!("OUT_DIR"), "/codegen.rs"));
-}
-
 pub use features::{LATEST_STABLE_RUST, RUST_TARGET_STRINGS, RustTarget};
 use features::RustFeatures;
 use ir::context::{BindgenContext, ItemId};
@@ -95,12 +90,6 @@ use std::path::{Path, PathBuf};
 use std::process::{Command, Stdio};
 use std::sync::Arc;
 
-use syntax::ast;
-use syntax::codemap::{DUMMY_SP, Span};
-use syntax::print::pp::eof;
-use syntax::print::pprust;
-use syntax::ptr::P;
-
 /// A type used to indicate which kind of items do we have to generate.
 ///
 /// TODO(emilio): Use `bitflags!`
@@ -948,7 +937,7 @@ impl Builder {
     }
 
     /// Generate the Rust bindings using the options built up thus far.
-    pub fn generate<'ctx>(mut self) -> Result<Bindings<'ctx>, ()> {
+    pub fn generate(mut self) -> Result<Bindings, ()> {
         self.options.input_header = self.input_headers.pop();
         self.options.clang_args.extend(
             self.input_headers
@@ -964,7 +953,7 @@ impl Builder {
             }),
         );
 
-        Bindings::generate(self.options, None)
+        Bindings::generate(self.options)
     }
 
     /// Preprocess and dump the input header files to disk.
@@ -1353,21 +1342,19 @@ fn ensure_libclang_is_loaded() {
 
 /// Generated Rust bindings.
 #[derive(Debug)]
-pub struct Bindings<'ctx> {
-    context: BindgenContext<'ctx>,
-    module: ast::Mod,
+pub struct Bindings {
+    context: BindgenContext,
+    module: quote::Tokens,
 }
 
-impl<'ctx> Bindings<'ctx> {
+impl Bindings {
     /// Generate bindings for the given options.
     ///
     /// Deprecated - use a `Builder` instead
     #[deprecated]
     pub fn generate(
         mut options: BindgenOptions,
-        span: Option<Span>,
-    ) -> Result<Bindings<'ctx>, ()> {
-        let span = span.unwrap_or(DUMMY_SP);
+    ) -> Result<Bindings, ()> {
         ensure_libclang_is_loaded();
 
         options.build();
@@ -1436,38 +1423,30 @@ impl<'ctx> Bindings<'ctx> {
 
         let time_phases = options.time_phases;
         let mut context = BindgenContext::new(options);
+
         {
             let _t = time::Timer::new("parse")
                                   .with_output(time_phases);
             try!(parse(&mut context));
         }
 
-        let module = ast::Mod {
-            inner: span,
-            items: codegen::codegen(&mut context),
-        };
+        let items = codegen::codegen(&mut context);
 
         Ok(Bindings {
             context: context,
-            module: module,
+            module: quote! {
+                #( #items )*
+            }
         })
     }
 
-    /// Convert these bindings into a Rust AST.
-    pub fn into_ast(self) -> Vec<P<ast::Item>> {
-        self.module.items
-    }
-
     /// Convert these bindings into source text (with raw lines prepended).
     pub fn to_string(&self) -> String {
-        let mut mod_str = vec![];
-        {
-            let ref_writer = Box::new(mod_str.by_ref()) as Box<Write>;
-            self.write(ref_writer).expect(
-                "Could not write bindings to string",
-            );
-        }
-        String::from_utf8(mod_str).unwrap()
+        let mut bytes = vec![];
+        self.write(Box::new(&mut bytes) as Box<Write>)
+            .expect("writing to a vec cannot fail");
+        String::from_utf8(bytes)
+            .expect("we should only write bindings that are valid utf-8")
     }
 
     /// Write these bindings as source text to a file.
@@ -1488,27 +1467,26 @@ impl<'ctx> Bindings<'ctx> {
 
     /// Write these bindings as source text to the given `Write`able.
     pub fn write<'a>(&self, mut writer: Box<Write + 'a>) -> io::Result<()> {
-        try!(writer.write(
+        writer.write(
             "/* automatically generated by rust-bindgen */\n\n".as_bytes(),
-        ));
+        )?;
 
         for line in self.context.options().raw_lines.iter() {
-            try!(writer.write(line.as_bytes()));
-            try!(writer.write("\n".as_bytes()));
+            writer.write(line.as_bytes())?;
+            writer.write("\n".as_bytes())?;
         }
         if !self.context.options().raw_lines.is_empty() {
-            try!(writer.write("\n".as_bytes()));
+            writer.write("\n".as_bytes())?;
         }
 
-        let mut ps = pprust::rust_printer(writer);
-        try!(ps.print_mod(&self.module, &[]));
-        try!(ps.print_remaining_comments());
-        try!(eof(&mut ps.s));
-        ps.s.out.flush()
+        writer.write(self.module.as_str().as_bytes())?;
+        Ok(())
     }
 
     /// Checks if rustfmt_bindings is set and runs rustfmt on the file
     fn rustfmt_generated_file(&self, file: &Path) -> io::Result<()> {
+        let _t = self.context.timer("rustfmt_generated_file");
+
         if !self.context.options().rustfmt_bindings {
             return Ok(());
         }
diff --git a/src/main.rs b/src/main.rs
index dc3572b3..eb3d6caf 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -4,7 +4,6 @@ extern crate env_logger;
 #[macro_use]
 #[cfg(feature = "logging")]
 extern crate log;
-extern crate clang_sys;
 extern crate clap;
 
 use bindgen::clang_version;
diff --git a/src/time.rs b/src/time.rs
index ebbac702..c841bccf 100644
--- a/src/time.rs
+++ b/src/time.rs
@@ -37,12 +37,12 @@ impl<'a> Timer<'a> {
     fn print_elapsed(&mut self) {
         if self.output {
             let elapsed = self.elapsed();
-            let time = (elapsed.as_secs() as f32)
-                       + (elapsed.subsec_nanos() as f32) / 1e9;
+            let time = (elapsed.as_secs() as f64) * 1e3
+                       + (elapsed.subsec_nanos() as f64) / 1e6;
             let stderr = io::stderr();
             // Arbitrary output format, subject to change.
             writeln!(stderr.lock(),
-                     "  time: {:.3} ms.\t{}",
+                     "  time: {:>9.3} ms.\t{}",
                      time, self.name)
                      .expect("timer write should not fail");
         }