Open
Description
Input C/C++ Header
typedef unsigned long long uint64_t;
template<typename T>
struct AlignedStorage2 {
union U {
char mBytes[sizeof(T)];
uint64_t mDummy;
} u;
};
struct Foo {
uint64_t a;
uint64_t b;
};
class Bar {
AlignedStorage2<Foo> m;
};Bindgen Invocation
$ bindgen input.hpp
Actual Results
#[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 AlignedStorage2 {
pub u: AlignedStorage2_U,
}
#[repr(C)]
#[derive(Debug, Copy, Clone)]
pub struct AlignedStorage2_U {
pub mBytes: __BindgenUnionField<*mut ::std::os::raw::c_char>,
pub mDummy: __BindgenUnionField<u64>,
pub bindgen_union_field: u64,
}
#[repr(C)]
#[derive(Debug, Copy)]
pub struct Foo {
pub a: u64,
pub b: u64,
}
#[test]
fn bindgen_test_layout_Foo() {
assert_eq!(::std::mem::size_of::<Foo>() , 16usize , concat ! (
"Size of: " , stringify ! ( Foo ) ));
assert_eq! (::std::mem::align_of::<Foo>() , 8usize , concat ! (
"Alignment of " , stringify ! ( Foo ) ));
assert_eq! (unsafe {
& ( * ( 0 as * const Foo ) ) . a as * const _ as usize } ,
0usize , concat ! (
"Alignment of field: " , stringify ! ( Foo ) , "::" ,
stringify ! ( a ) ));
assert_eq! (unsafe {
& ( * ( 0 as * const Foo ) ) . b as * const _ as usize } ,
8usize , concat ! (
"Alignment of field: " , stringify ! ( Foo ) , "::" ,
stringify ! ( b ) ));
}
impl Clone for Foo {
fn clone(&self) -> Self { *self }
}
#[repr(C)]
#[derive(Debug, Copy)]
pub struct Bar {
pub m: AlignedStorage2,
}
#[test]
fn bindgen_test_layout_Bar() {
assert_eq!(::std::mem::size_of::<Bar>() , 16usize , concat ! (
"Size of: " , stringify ! ( Bar ) ));
assert_eq! (::std::mem::align_of::<Bar>() , 8usize , concat ! (
"Alignment of " , stringify ! ( Bar ) ));
assert_eq! (unsafe {
& ( * ( 0 as * const Bar ) ) . m as * const _ as usize } ,
0usize , concat ! (
"Alignment of field: " , stringify ! ( Bar ) , "::" ,
stringify ! ( m ) ));
}
impl Clone for Bar {
fn clone(&self) -> Self { *self }
}
#[test]
fn __bindgen_test_layout_AlignedStorage2_open0_Foo_close0_instantiation() {
assert_eq!(::std::mem::size_of::<AlignedStorage2>() , 16usize , concat ! (
"Size of template specialization: " , stringify ! (
AlignedStorage2 ) ));
assert_eq!(::std::mem::align_of::<AlignedStorage2>() , 8usize , concat ! (
"Alignment of template specialization: " , stringify ! (
AlignedStorage2 ) ));
}Expected Results
In the generated code above, the size of AlignedStorage2 is 8 bytes, but in the layout test, it asserts the size is 16 bytes, which is the correct size for the original C++ struct.
I'm not sure what should we do here. I guess it is possible for bindgen to generate the correct size for AlignedStorage2.