check layout align before padding bytes

src/codegen/struct_layout.rs

@@ -89,9 +89,12 @@ impl<'a, 'ctx> StructLayoutTracker<'a, 'ctx> {
                     Some(offset) if offset / 8  > self.latest_offset => {
                         (offset / 8  - self.latest_offset, true)
                     }
-                    _ => {
+                    _ if field_layout.align != 0 => {
                         (self.padding_bytes(field_layout), (self.latest_offset % field_layout.align) != 0)
                     }
+                    _ => {
+                        (0, false)
+                    }
                 };
 
                 self.latest_offset += padding_bytes;

tests/expectations/tests/issue-493.rs

@@ -0,0 +1,152 @@
+/* automatically generated by rust-bindgen */
+
+
+#![allow(non_snake_case)]
+
+
+#[repr(C)]
+pub struct __BindgenUnionField<T>(::std::marker::PhantomData<T>);
+impl <T> __BindgenUnionField<T> {
+    #[inline]
+    pub fn new() -> Self { __BindgenUnionField(::std::marker::PhantomData) }
+    #[inline]
+    pub unsafe fn as_ref(&self) -> &T { ::std::mem::transmute(self) }
+    #[inline]
+    pub unsafe fn as_mut(&mut self) -> &mut T { ::std::mem::transmute(self) }
+}
+impl <T> ::std::default::Default for __BindgenUnionField<T> {
+    #[inline]
+    fn default() -> Self { Self::new() }
+}
+impl <T> ::std::clone::Clone for __BindgenUnionField<T> {
+    #[inline]
+    fn clone(&self) -> Self { Self::new() }
+}
+impl <T> ::std::marker::Copy for __BindgenUnionField<T> { }
+impl <T> ::std::fmt::Debug for __BindgenUnionField<T> {
+    fn fmt(&self, fmt: &mut ::std::fmt::Formatter) -> ::std::fmt::Result {
+        fmt.write_str("__BindgenUnionField")
+    }
+}
+#[repr(C)]
+#[derive(Debug, Copy, Clone)]
+pub struct basic_string<_CharT, _Traits, _Allocator> {
+    pub _address: u8,
+    pub _phantom_0: ::std::marker::PhantomData<_CharT>,
+    pub _phantom_1: ::std::marker::PhantomData<_Traits>,
+    pub _phantom_2: ::std::marker::PhantomData<_Allocator>,
+}
+pub type basic_string_size_type = ::std::os::raw::c_ulonglong;
+pub type basic_string_value_type = ::std::os::raw::c_char;
+pub type basic_string_pointer = *mut basic_string_value_type;
+#[repr(C)]
+#[derive(Debug, Copy, Clone)]
+pub struct basic_string___long<_CharT, _Traits, _Allocator> {
+    pub __cap_: basic_string_size_type,
+    pub __size_: basic_string_size_type,
+    pub __data_: basic_string_pointer,
+    pub _phantom_0: ::std::marker::PhantomData<_CharT>,
+    pub _phantom_1: ::std::marker::PhantomData<_Traits>,
+    pub _phantom_2: ::std::marker::PhantomData<_Allocator>,
+}
+impl <_CharT, _Traits, _Allocator> Default for
+ basic_string___long<_CharT, _Traits, _Allocator> {
+    fn default() -> Self { unsafe { ::std::mem::zeroed() } }
+}
+pub const basic_string___min_cap: basic_string__bindgen_ty_1 =
+    basic_string__bindgen_ty_1::__min_cap;
+#[repr(i32)]
+#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
+pub enum basic_string__bindgen_ty_1 { __min_cap = 0, }
+#[repr(C)]
+#[derive(Debug, Copy, Clone)]
+pub struct basic_string___short<_CharT, _Traits, _Allocator> {
+    pub __bindgen_anon_1: basic_string___short__bindgen_ty_1<_CharT, _Traits,
+                                                             _Allocator>,
+    pub __data_: *mut basic_string_value_type,
+    pub _phantom_0: ::std::marker::PhantomData<_CharT>,
+    pub _phantom_1: ::std::marker::PhantomData<_Traits>,
+    pub _phantom_2: ::std::marker::PhantomData<_Allocator>,
+}
+#[repr(C)]
+#[derive(Debug, Default, Copy, Clone)]
+pub struct basic_string___short__bindgen_ty_1<_CharT, _Traits, _Allocator> {
+    pub __size_: __BindgenUnionField<::std::os::raw::c_uchar>,
+    pub __lx: __BindgenUnionField<basic_string_value_type>,
+    pub bindgen_union_field: u8,
+    pub _phantom_0: ::std::marker::PhantomData<_CharT>,
+    pub _phantom_1: ::std::marker::PhantomData<_Traits>,
+    pub _phantom_2: ::std::marker::PhantomData<_Allocator>,
+}
+impl <_CharT, _Traits, _Allocator> Default for
+ basic_string___short<_CharT, _Traits, _Allocator> {
+    fn default() -> Self { unsafe { ::std::mem::zeroed() } }
+}
+#[repr(C)]
+#[derive(Copy, Clone)]
+pub struct basic_string___ulx<_CharT, _Traits, _Allocator> {
+    pub __lx: __BindgenUnionField<basic_string___long<_CharT, _Traits,
+                                                      _Allocator>>,
+    pub __lxx: __BindgenUnionField<basic_string___short<_CharT, _Traits,
+                                                        _Allocator>>,
+    pub bindgen_union_field: [u8; 0usize],
+    pub _phantom_0: ::std::marker::PhantomData<_CharT>,
+    pub _phantom_1: ::std::marker::PhantomData<_Traits>,
+    pub _phantom_2: ::std::marker::PhantomData<_Allocator>,
+}
+impl <_CharT, _Traits, _Allocator> Default for
+ basic_string___ulx<_CharT, _Traits, _Allocator> {
+    fn default() -> Self { unsafe { ::std::mem::zeroed() } }
+}
+pub const basic_string___n_words: basic_string__bindgen_ty_2 =
+    basic_string__bindgen_ty_2::__n_words;
+#[repr(i32)]
+#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
+pub enum basic_string__bindgen_ty_2 { __n_words = 0, }
+#[repr(C)]
+#[derive(Debug, Copy, Clone)]
+pub struct basic_string___raw<_CharT, _Traits, _Allocator> {
+    pub __words: *mut basic_string_size_type,
+    pub _phantom_0: ::std::marker::PhantomData<_CharT>,
+    pub _phantom_1: ::std::marker::PhantomData<_Traits>,
+    pub _phantom_2: ::std::marker::PhantomData<_Allocator>,
+}
+impl <_CharT, _Traits, _Allocator> Default for
+ basic_string___raw<_CharT, _Traits, _Allocator> {
+    fn default() -> Self { unsafe { ::std::mem::zeroed() } }
+}
+#[repr(C)]
+#[derive(Copy, Clone)]
+pub struct basic_string___rep<_CharT, _Traits, _Allocator> {
+    pub __bindgen_anon_1: basic_string___rep__bindgen_ty_1<_CharT, _Traits,
+                                                           _Allocator>,
+    pub _phantom_0: ::std::marker::PhantomData<_CharT>,
+    pub _phantom_1: ::std::marker::PhantomData<_Traits>,
+    pub _phantom_2: ::std::marker::PhantomData<_Allocator>,
+}
+#[repr(C)]
+#[derive(Copy, Clone)]
+pub struct basic_string___rep__bindgen_ty_1<_CharT, _Traits, _Allocator> {
+    pub __l: __BindgenUnionField<basic_string___long<_CharT, _Traits,
+                                                     _Allocator>>,
+    pub __s: __BindgenUnionField<basic_string___short<_CharT, _Traits,
+                                                      _Allocator>>,
+    pub __r: __BindgenUnionField<basic_string___raw<_CharT, _Traits,
+                                                    _Allocator>>,
+    pub bindgen_union_field: [u8; 0usize],
+    pub _phantom_0: ::std::marker::PhantomData<_CharT>,
+    pub _phantom_1: ::std::marker::PhantomData<_Traits>,
+    pub _phantom_2: ::std::marker::PhantomData<_Allocator>,
+}
+impl <_CharT, _Traits, _Allocator> Default for
+ basic_string___rep__bindgen_ty_1<_CharT, _Traits, _Allocator> {
+    fn default() -> Self { unsafe { ::std::mem::zeroed() } }
+}
+impl <_CharT, _Traits, _Allocator> Default for
+ basic_string___rep<_CharT, _Traits, _Allocator> {
+    fn default() -> Self { unsafe { ::std::mem::zeroed() } }
+}
+impl <_CharT, _Traits, _Allocator> Default for
+ basic_string<_CharT, _Traits, _Allocator> {
+    fn default() -> Self { unsafe { ::std::mem::zeroed() } }
+}

tests/headers/issue-493.hpp

@@ -0,0 +1,47 @@
+template<class _CharT, class _Traits, class _Allocator>
+class basic_string
+{
+public:
+    typedef unsigned long long size_type;
+    typedef char value_type;
+    typedef value_type * pointer;
+
+    struct __long
+    {
+        size_type __cap_;
+        size_type __size_;
+        pointer   __data_;
+    };
+
+    enum {__min_cap = (sizeof(__long) - 1)/sizeof(value_type) > 2 ?
+                        (sizeof(__long) - 1)/sizeof(value_type) : 2};
+
+    struct __short
+    {
+        union
+        {
+            unsigned char __size_;
+            value_type __lx;
+        };
+        value_type __data_[__min_cap];
+    };
+
+    union __ulx{__long __lx; __short __lxx;};
+
+    enum {__n_words = sizeof(__ulx) / sizeof(size_type)};
+
+    struct __raw
+    {
+        size_type __words[__n_words];
+    };
+
+    struct __rep
+    {
+        union
+        {
+            __long  __l;
+            __short __s;
+            __raw   __r;
+        };
+    };
+};