Identify forward declarations in params. (#2052)

2 files changed, 44 insertions, 0 deletions

diff --git a/tests/expectations/tests/parm-union.rs b/tests/expectations/tests/parm-union.rs
new file mode 100644
index 00000000..9f7dd20a
--- /dev/null
+++ b/tests/expectations/tests/parm-union.rs
@@ -0,0 +1,40 @@
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
+
+#[repr(C)]
+#[derive(Debug, Default, Copy, Clone)]
+pub struct Struct {
+    pub _address: u8,
+}
+#[test]
+fn bindgen_test_layout_Struct() {
+    assert_eq!(
+        ::std::mem::size_of::<Struct>(),
+        1usize,
+        concat!("Size of: ", stringify!(Struct))
+    );
+    assert_eq!(
+        ::std::mem::align_of::<Struct>(),
+        1usize,
+        concat!("Alignment of ", stringify!(Struct))
+    );
+}
+extern "C" {
+    #[link_name = "\u{1}_ZN6Struct8FunctionER5Union"]
+    pub fn Struct_Function(this: *mut Struct, arg1: *mut Union);
+}
+impl Struct {
+    #[inline]
+    pub unsafe fn Function(&mut self, arg1: *mut Union) {
+        Struct_Function(self, arg1)
+    }
+}
+#[repr(C)]
+#[derive(Copy, Clone)]
+pub struct Union {
+    _unused: [u8; 0],
+}
diff --git a/tests/headers/parm-union.hpp b/tests/headers/parm-union.hpp
new file mode 100644
index 00000000..e36df691
--- /dev/null
+++ b/tests/headers/parm-union.hpp
@@ -0,0 +1,4 @@
+struct Struct
+{
+    void Function(union Union&);
+};