Auto merge of #656 - emilio:fn-collision, r=fitzgen

codegen: Change forward-declared types to avoid collisions with functions.

Fixes #654

7 files changed, 38 insertions, 7 deletions

diff --git a/src/codegen/mod.rs b/src/codegen/mod.rs
index a5df8945..39b115fa 100644
--- a/src/codegen/mod.rs
+++ b/src/codegen/mod.rs
@@ -1047,13 +1047,16 @@ impl CodeGenerator for CompInfo {
 
         // generate tuple struct if struct or union is a forward declaration,
         // skip for now if template parameters are needed.
+        //
+        // NB: We generate a proper struct to avoid struct/function name
+        // 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([u8; 0]);
+                                           pub struct $struct_name { _unused: [u8; 0] };
                                           )
                 .unwrap();
             result.push(tuple_struct);
diff --git a/tests/expectations/tests/forward-declaration-autoptr.rs b/tests/expectations/tests/forward-declaration-autoptr.rs
index b05984c8..d3729bed 100644
--- a/tests/expectations/tests/forward-declaration-autoptr.rs
+++ b/tests/expectations/tests/forward-declaration-autoptr.rs
@@ -6,7 +6,9 @@
 
 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
-pub struct Foo([u8; 0]);
+pub struct Foo {
+    _unused: [u8; 0],
+}
 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
 pub struct RefPtr<T> {
diff --git a/tests/expectations/tests/forward_declared_complex_types.rs b/tests/expectations/tests/forward_declared_complex_types.rs
index a6e67f7b..03330b2f 100644
--- a/tests/expectations/tests/forward_declared_complex_types.rs
+++ b/tests/expectations/tests/forward_declared_complex_types.rs
@@ -21,7 +21,9 @@ impl Clone for Foo_empty {
 }
 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
-pub struct Foo([u8; 0]);
+pub struct Foo {
+    _unused: [u8; 0],
+}
 #[repr(C)]
 #[derive(Debug, Copy)]
 pub struct Bar {
@@ -51,14 +53,18 @@ extern "C" {
 }
 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
-pub struct Union([u8; 0]);
+pub struct Union {
+    _unused: [u8; 0],
+}
 extern "C" {
     #[link_name = "_Z9baz_unionP5Union"]
     pub fn baz_union(u: *mut Union);
 }
 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
-pub struct Quux([u8; 0]);
+pub struct Quux {
+    _unused: [u8; 0],
+}
 extern "C" {
     #[link_name = "_Z9baz_classP4Quux"]
     pub fn baz_class(q: *mut Quux);
diff --git a/tests/expectations/tests/issue-654-struct-fn-collision.rs b/tests/expectations/tests/issue-654-struct-fn-collision.rs
new file mode 100644
index 00000000..c2915b3f
--- /dev/null
+++ b/tests/expectations/tests/issue-654-struct-fn-collision.rs
@@ -0,0 +1,14 @@
+/* automatically generated by rust-bindgen */
+
+
+#![allow(non_snake_case)]
+
+
+#[repr(C)]
+#[derive(Debug, Copy, Clone)]
+pub struct foo {
+    _unused: [u8; 0],
+}
+extern "C" {
+    pub fn foo() -> ::std::os::raw::c_int;
+}
diff --git a/tests/expectations/tests/layout_array.rs b/tests/expectations/tests/layout_array.rs
index 2cc85785..0f9944e8 100644
--- a/tests/expectations/tests/layout_array.rs
+++ b/tests/expectations/tests/layout_array.rs
@@ -10,7 +10,9 @@ pub const RTE_MEMPOOL_MAX_OPS_IDX: ::std::os::raw::c_uint = 16;
 pub const RTE_HEAP_NUM_FREELISTS: ::std::os::raw::c_uint = 13;
 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
-pub struct rte_mempool([u8; 0]);
+pub struct rte_mempool {
+    _unused: [u8; 0],
+}
 /**
  * Prototype for implementation specific data provisioning function.
  *
diff --git a/tests/expectations/tests/same_struct_name_in_different_namespaces.rs b/tests/expectations/tests/same_struct_name_in_different_namespaces.rs
index 820b5e71..6ea05143 100644
--- a/tests/expectations/tests/same_struct_name_in_different_namespaces.rs
+++ b/tests/expectations/tests/same_struct_name_in_different_namespaces.rs
@@ -6,7 +6,9 @@
 
 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
-pub struct JS_Zone([u8; 0]);
+pub struct JS_Zone {
+    _unused: [u8; 0],
+}
 #[repr(C)]
 #[derive(Debug, Default, Copy)]
 pub struct JS_shadow_Zone {
diff --git a/tests/headers/issue-654-struct-fn-collision.h b/tests/headers/issue-654-struct-fn-collision.h
new file mode 100644
index 00000000..f52a1b20
--- /dev/null
+++ b/tests/headers/issue-654-struct-fn-collision.h
@@ -0,0 +1,2 @@
+struct foo;
+int foo(void);