--wrap-static-fns emits incomplete struct _bindgen_ty_N for anonymous record parameters

[lwz23]

Input C/C++ Header

static int take(struct { int x; int y; } s, int t) { return s.x + t; }

Bindgen Invocation

$ bindgen input.h --wrap-static-fns --wrap-static-fns-path wrap -- -x c -std=gnu11

Actual Results

bindgen exits 0. The generated wrapper is:

#include "input.h"

int take__extern(struct _bindgen_ty_1 s, int t) { return take(s, t); }

struct _bindgen_ty_1 is not in the header. clang:

wrap.c:5:25: warning: declaration of 'struct _bindgen_ty_1' will not be visible outside of this function
wrap.c:5:39: error: variable has incomplete type 'struct _bindgen_ty_1'

codegen/serialize.rs prints struct {canonical_name} for TypeKind::Comp. For an anonymous record that name is _bindgen_ty_N. A named struct S { int x; int y; } wrapper prints struct S and compiles.

Same thing for an anonymous union (union _bindgen_ty_1).

This is not #3403 (pointer-to-array declarators) or #2805 (_Bool vs bool).

Expected Results

The wrapper should use a C type that is complete after #include "input.h" (the original anonymous type, or a tag defined in the wrapper).

Environment

bindgen: 0.73.1 (rust-lang/rust-bindgen 77cbc723)
clang/libclang: Homebrew clang 21.1.8
rustc: 1.97.1
target: aarch64-apple-darwin
OS: macOS