codegen: Make zero-sized arrays affect alignment.

Fixes #684

10 files changed, 141 insertions, 41 deletions

diff --git a/src/codegen/mod.rs b/src/codegen/mod.rs
index 9a7bf897..f189fc69 100644
--- a/src/codegen/mod.rs
+++ b/src/codegen/mod.rs
@@ -3740,14 +3740,14 @@ mod utils {
             #[repr(C)]
             #[derive(Default)]
             pub struct __IncompleteArrayField<T>(
-                ::#prefix::marker::PhantomData<T>);
+                ::#prefix::marker::PhantomData<T>, [T; 0]);
         };
 
         let incomplete_array_impl = quote! {
             impl<T> __IncompleteArrayField<T> {
                 #[inline]
                 pub fn new() -> Self {
-                    __IncompleteArrayField(::#prefix::marker::PhantomData)
+                    __IncompleteArrayField(::#prefix::marker::PhantomData, [])
                 }
 
                 #[inline]
@@ -3790,15 +3790,10 @@ mod utils {
             }
         };
 
-        let incomplete_array_copy_impl = quote! {
-            impl<T> ::#prefix::marker::Copy for __IncompleteArrayField<T> {}
-        };
-
         let items = vec![incomplete_array_decl,
                          incomplete_array_impl,
                          incomplete_array_debug_impl,
-                         incomplete_array_clone_impl,
-                         incomplete_array_copy_impl];
+                         incomplete_array_clone_impl];
 
         let old_items = mem::replace(result, items);
         result.extend(old_items.into_iter());
diff --git a/tests/expectations/tests/class.rs b/tests/expectations/tests/class.rs
index f7639aac..f52f0f85 100644
--- a/tests/expectations/tests/class.rs
+++ b/tests/expectations/tests/class.rs
@@ -1,16 +1,19 @@
 /* automatically generated by rust-bindgen */
 
-
-#![allow(dead_code, non_snake_case, non_camel_case_types, non_upper_case_globals)]
-
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
 
 #[repr(C)]
 #[derive(Default)]
-pub struct __IncompleteArrayField<T>(::std::marker::PhantomData<T>);
+pub struct __IncompleteArrayField<T>(::std::marker::PhantomData<T>, [T; 0]);
 impl<T> __IncompleteArrayField<T> {
     #[inline]
     pub fn new() -> Self {
-        __IncompleteArrayField(::std::marker::PhantomData)
+        __IncompleteArrayField(::std::marker::PhantomData, [])
     }
     #[inline]
     pub unsafe fn as_ptr(&self) -> *const T {
@@ -40,7 +43,6 @@ impl<T> ::std::clone::Clone for __IncompleteArrayField<T> {
         Self::new()
     }
 }
-impl<T> ::std::marker::Copy for __IncompleteArrayField<T> {}
 #[repr(C)]
 #[derive(Copy, Clone)]
 pub struct C {
diff --git a/tests/expectations/tests/class_1_0.rs b/tests/expectations/tests/class_1_0.rs
index a5639b25..b35e8814 100644
--- a/tests/expectations/tests/class_1_0.rs
+++ b/tests/expectations/tests/class_1_0.rs
@@ -1,16 +1,19 @@
 /* automatically generated by rust-bindgen */
 
-
-#![allow(dead_code, non_snake_case, non_camel_case_types, non_upper_case_globals)]
-
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
 
 #[repr(C)]
 #[derive(Default)]
-pub struct __IncompleteArrayField<T>(::std::marker::PhantomData<T>);
+pub struct __IncompleteArrayField<T>(::std::marker::PhantomData<T>, [T; 0]);
 impl<T> __IncompleteArrayField<T> {
     #[inline]
     pub fn new() -> Self {
-        __IncompleteArrayField(::std::marker::PhantomData)
+        __IncompleteArrayField(::std::marker::PhantomData, [])
     }
     #[inline]
     pub unsafe fn as_ptr(&self) -> *const T {
@@ -40,7 +43,6 @@ impl<T> ::std::clone::Clone for __IncompleteArrayField<T> {
         Self::new()
     }
 }
-impl<T> ::std::marker::Copy for __IncompleteArrayField<T> {}
 #[repr(C)]
 pub struct __BindgenUnionField<T>(::std::marker::PhantomData<T>);
 impl<T> __BindgenUnionField<T> {
diff --git a/tests/expectations/tests/derive-hash-struct-with-incomplete-array.rs b/tests/expectations/tests/derive-hash-struct-with-incomplete-array.rs
index e95c3391..8e87432f 100644
--- a/tests/expectations/tests/derive-hash-struct-with-incomplete-array.rs
+++ b/tests/expectations/tests/derive-hash-struct-with-incomplete-array.rs
@@ -1,16 +1,19 @@
 /* automatically generated by rust-bindgen */
 
-
-#![allow(dead_code, non_snake_case, non_camel_case_types, non_upper_case_globals)]
-
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
 
 #[repr(C)]
 #[derive(Default)]
-pub struct __IncompleteArrayField<T>(::std::marker::PhantomData<T>);
+pub struct __IncompleteArrayField<T>(::std::marker::PhantomData<T>, [T; 0]);
 impl<T> __IncompleteArrayField<T> {
     #[inline]
     pub fn new() -> Self {
-        __IncompleteArrayField(::std::marker::PhantomData)
+        __IncompleteArrayField(::std::marker::PhantomData, [])
     }
     #[inline]
     pub unsafe fn as_ptr(&self) -> *const T {
@@ -40,7 +43,6 @@ impl<T> ::std::clone::Clone for __IncompleteArrayField<T> {
         Self::new()
     }
 }
-impl<T> ::std::marker::Copy for __IncompleteArrayField<T> {}
 #[repr(C)]
 #[derive(Debug, Default)]
 pub struct test {
diff --git a/tests/expectations/tests/issue-643-inner-struct.rs b/tests/expectations/tests/issue-643-inner-struct.rs
index 83b52c22..a9696a6d 100644
--- a/tests/expectations/tests/issue-643-inner-struct.rs
+++ b/tests/expectations/tests/issue-643-inner-struct.rs
@@ -1,16 +1,19 @@
 /* automatically generated by rust-bindgen */
 
-
-#![allow(dead_code, non_snake_case, non_camel_case_types, non_upper_case_globals)]
-
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
 
 #[repr(C)]
 #[derive(Default)]
-pub struct __IncompleteArrayField<T>(::std::marker::PhantomData<T>);
+pub struct __IncompleteArrayField<T>(::std::marker::PhantomData<T>, [T; 0]);
 impl<T> __IncompleteArrayField<T> {
     #[inline]
     pub fn new() -> Self {
-        __IncompleteArrayField(::std::marker::PhantomData)
+        __IncompleteArrayField(::std::marker::PhantomData, [])
     }
     #[inline]
     pub unsafe fn as_ptr(&self) -> *const T {
@@ -40,7 +43,6 @@ impl<T> ::std::clone::Clone for __IncompleteArrayField<T> {
         Self::new()
     }
 }
-impl<T> ::std::marker::Copy for __IncompleteArrayField<T> {}
 #[repr(C)]
 #[derive(Debug)]
 pub struct rte_ring {
diff --git a/tests/expectations/tests/layout_align.rs b/tests/expectations/tests/layout_align.rs
index a1350b14..39fb2948 100644
--- a/tests/expectations/tests/layout_align.rs
+++ b/tests/expectations/tests/layout_align.rs
@@ -91,11 +91,11 @@ where
 }
 #[repr(C)]
 #[derive(Default)]
-pub struct __IncompleteArrayField<T>(::std::marker::PhantomData<T>);
+pub struct __IncompleteArrayField<T>(::std::marker::PhantomData<T>, [T; 0]);
 impl<T> __IncompleteArrayField<T> {
     #[inline]
     pub fn new() -> Self {
-        __IncompleteArrayField(::std::marker::PhantomData)
+        __IncompleteArrayField(::std::marker::PhantomData, [])
     }
     #[inline]
     pub unsafe fn as_ptr(&self) -> *const T {
@@ -125,7 +125,6 @@ impl<T> ::std::clone::Clone for __IncompleteArrayField<T> {
         Self::new()
     }
 }
-impl<T> ::std::marker::Copy for __IncompleteArrayField<T> {}
 #[repr(C)]
 #[derive(Debug)]
 pub struct rte_kni_fifo {
diff --git a/tests/expectations/tests/layout_large_align_field.rs b/tests/expectations/tests/layout_large_align_field.rs
index 5a865189..8b7be4ca 100644
--- a/tests/expectations/tests/layout_large_align_field.rs
+++ b/tests/expectations/tests/layout_large_align_field.rs
@@ -9,11 +9,11 @@
 
 #[repr(C)]
 #[derive(Default)]
-pub struct __IncompleteArrayField<T>(::std::marker::PhantomData<T>);
+pub struct __IncompleteArrayField<T>(::std::marker::PhantomData<T>, [T; 0]);
 impl<T> __IncompleteArrayField<T> {
     #[inline]
     pub fn new() -> Self {
-        __IncompleteArrayField(::std::marker::PhantomData)
+        __IncompleteArrayField(::std::marker::PhantomData, [])
     }
     #[inline]
     pub unsafe fn as_ptr(&self) -> *const T {
@@ -43,7 +43,6 @@ impl<T> ::std::clone::Clone for __IncompleteArrayField<T> {
         Self::new()
     }
 }
-impl<T> ::std::marker::Copy for __IncompleteArrayField<T> {}
 pub const RTE_CACHE_LINE_SIZE: u32 = 64;
 pub const RTE_LIBRTE_IP_FRAG_MAX_FRAG: u32 = 4;
 pub const IP_LAST_FRAG_IDX: _bindgen_ty_1 = _bindgen_ty_1::IP_LAST_FRAG_IDX;
diff --git a/tests/expectations/tests/zero-size-array-align.rs b/tests/expectations/tests/zero-size-array-align.rs
new file mode 100644
index 00000000..9c60d14e
--- /dev/null
+++ b/tests/expectations/tests/zero-size-array-align.rs
@@ -0,0 +1,95 @@
+/* automatically generated by rust-bindgen */
+
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
+
+#[repr(C)]
+#[derive(Default)]
+pub struct __IncompleteArrayField<T>(::std::marker::PhantomData<T>, [T; 0]);
+impl<T> __IncompleteArrayField<T> {
+    #[inline]
+    pub fn new() -> Self {
+        __IncompleteArrayField(::std::marker::PhantomData, [])
+    }
+    #[inline]
+    pub unsafe fn as_ptr(&self) -> *const T {
+        ::std::mem::transmute(self)
+    }
+    #[inline]
+    pub unsafe fn as_mut_ptr(&mut self) -> *mut T {
+        ::std::mem::transmute(self)
+    }
+    #[inline]
+    pub unsafe fn as_slice(&self, len: usize) -> &[T] {
+        ::std::slice::from_raw_parts(self.as_ptr(), len)
+    }
+    #[inline]
+    pub unsafe fn as_mut_slice(&mut self, len: usize) -> &mut [T] {
+        ::std::slice::from_raw_parts_mut(self.as_mut_ptr(), len)
+    }
+}
+impl<T> ::std::fmt::Debug for __IncompleteArrayField<T> {
+    fn fmt(&self, fmt: &mut ::std::fmt::Formatter<'_>) -> ::std::fmt::Result {
+        fmt.write_str("__IncompleteArrayField")
+    }
+}
+impl<T> ::std::clone::Clone for __IncompleteArrayField<T> {
+    #[inline]
+    fn clone(&self) -> Self {
+        Self::new()
+    }
+}
+#[repr(C)]
+#[derive(Debug, Default)]
+pub struct dm_deps {
+    pub count: ::std::os::raw::c_uint,
+    pub filler: ::std::os::raw::c_uint,
+    pub device: __IncompleteArrayField<::std::os::raw::c_ulonglong>,
+}
+#[test]
+fn bindgen_test_layout_dm_deps() {
+    assert_eq!(
+        ::std::mem::size_of::<dm_deps>(),
+        8usize,
+        concat!("Size of: ", stringify!(dm_deps))
+    );
+    assert_eq!(
+        ::std::mem::align_of::<dm_deps>(),
+        8usize,
+        concat!("Alignment of ", stringify!(dm_deps))
+    );
+    assert_eq!(
+        unsafe { &(*(::std::ptr::null::<dm_deps>())).count as *const _ as usize },
+        0usize,
+        concat!(
+            "Offset of field: ",
+            stringify!(dm_deps),
+            "::",
+            stringify!(count)
+        )
+    );
+    assert_eq!(
+        unsafe { &(*(::std::ptr::null::<dm_deps>())).filler as *const _ as usize },
+        4usize,
+        concat!(
+            "Offset of field: ",
+            stringify!(dm_deps),
+            "::",
+            stringify!(filler)
+        )
+    );
+    assert_eq!(
+        unsafe { &(*(::std::ptr::null::<dm_deps>())).device as *const _ as usize },
+        8usize,
+        concat!(
+            "Offset of field: ",
+            stringify!(dm_deps),
+            "::",
+            stringify!(device)
+        )
+    );
+}
diff --git a/tests/expectations/tests/zero-sized-array.rs b/tests/expectations/tests/zero-sized-array.rs
index 4464bb4b..e002251d 100644
--- a/tests/expectations/tests/zero-sized-array.rs
+++ b/tests/expectations/tests/zero-sized-array.rs
@@ -9,11 +9,11 @@
 
 #[repr(C)]
 #[derive(Default)]
-pub struct __IncompleteArrayField<T>(::std::marker::PhantomData<T>);
+pub struct __IncompleteArrayField<T>(::std::marker::PhantomData<T>, [T; 0]);
 impl<T> __IncompleteArrayField<T> {
     #[inline]
     pub fn new() -> Self {
-        __IncompleteArrayField(::std::marker::PhantomData)
+        __IncompleteArrayField(::std::marker::PhantomData, [])
     }
     #[inline]
     pub unsafe fn as_ptr(&self) -> *const T {
@@ -43,7 +43,6 @@ impl<T> ::std::clone::Clone for __IncompleteArrayField<T> {
         Self::new()
     }
 }
-impl<T> ::std::marker::Copy for __IncompleteArrayField<T> {}
 /// Bizarrely enough, this should *not* get an `_address` field.
 #[repr(C)]
 #[derive(Debug, Default)]
diff --git a/tests/headers/zero-size-array-align.h b/tests/headers/zero-size-array-align.h
new file mode 100644
index 00000000..05b11bce
--- /dev/null
+++ b/tests/headers/zero-size-array-align.h
@@ -0,0 +1,5 @@
+struct dm_deps {
+  unsigned count;
+  unsigned filler;
+  unsigned long long device[0];
+};