Open
Description
This bizarre edge case in a library I'm consuming has caused bindgen to segfault. I've simplified it the best I can:
// input.h
template<typename T, typename... U> union Foo {
Foo<U...> foo;
};I get no output from bindgen, just a segfault:
$ bindgen input.h -- -x c++
zsh: segmentation fault (core dumped) bindgen input.h -- -x c++
I know that C++ templates (and especially variadic templates) are beyond the scope of bindgen, but I believe that it would probably be better if it output "Unhandled cursor kind" or something along those lines.
Some other notes for debugging:
-
--blacklist-type Fooworks, but discovering the type when it's buried deep in a library's header files takes a while (speaking from experience 😉) -
Removing
Tfrom the template does not invoke a segfault:template<typename... U> union Foo { Foo<U...> foo; };
Bindgen output
/* automatically generated by rust-bindgen 0.54.1 */ #[repr(C)] pub struct __BindgenUnionField<T>(::std::marker::PhantomData<T>); impl<T> __BindgenUnionField<T> { #[inline] pub const 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") } } impl<T> ::std::hash::Hash for __BindgenUnionField<T> { fn hash<H: ::std::hash::Hasher>(&self, _state: &mut H) {} } impl<T> ::std::cmp::PartialEq for __BindgenUnionField<T> { fn eq(&self, _other: &__BindgenUnionField<T>) -> bool { true } } impl<T> ::std::cmp::Eq for __BindgenUnionField<T> {} #[repr(C)] pub struct Foo { pub foo: __BindgenUnionField<Foo>, pub bindgen_union_field: [u8; 0usize], }