Avoid case of a self-referential type alias.

src/ir/ty.rs

@@ -1120,7 +1120,16 @@ impl Type {
                     let inner = cursor.typedef_type().expect("Not valid Type?");
                     let inner =
                         Item::from_ty_or_ref(inner, location, None, ctx);
-                    TypeKind::Alias(inner)
+                    if inner == potential_id {
+                        warn!(
+                            "Generating oqaque type instead of self-referential \
+                            typedef");
+                        // This can happen if we bail out of recursive situations
+                        // within the clang parsing.
+                        TypeKind::Opaque
+                    } else {
+                        TypeKind::Alias(inner)
+                    }
                 }
                 CXType_Enum => {
                     let enum_ = Enum::from_ty(ty, ctx).expect("Not an enum?");

tests/expectations/tests/constified-enum-module-overflow.rs

@@ -0,0 +1,54 @@
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
+
+#[repr(C)]
+#[derive(Debug, Default, Copy, Clone)]
+pub struct B {
+    pub _address: u8,
+}
+#[repr(C)]
+#[derive(Debug, Default, Copy, Clone)]
+pub struct C {
+    pub _address: u8,
+}
+pub type C_U = B;
+#[repr(C)]
+#[derive(Debug, Default, Copy, Clone)]
+pub struct A {
+    pub u: u8,
+}
+#[test]
+fn bindgen_test_layout_A() {
+    assert_eq!(
+        ::std::mem::size_of::<A>(),
+        1usize,
+        concat!("Size of: ", stringify!(A))
+    );
+    assert_eq!(
+        ::std::mem::align_of::<A>(),
+        1usize,
+        concat!("Alignment of ", stringify!(A))
+    );
+    assert_eq!(
+        unsafe { &(*(::std::ptr::null::<A>())).u as *const _ as usize },
+        0usize,
+        concat!("Offset of field: ", stringify!(A), "::", stringify!(u))
+    );
+}
+#[test]
+fn __bindgen_test_layout_C_open0_A_close0_instantiation() {
+    assert_eq!(
+        ::std::mem::size_of::<C>(),
+        1usize,
+        concat!("Size of template specialization: ", stringify!(C))
+    );
+    assert_eq!(
+        ::std::mem::align_of::<C>(),
+        1usize,
+        concat!("Alignment of template specialization: ", stringify!(C))
+    );
+}

tests/headers/constified-enum-module-overflow.hpp

@@ -0,0 +1,8 @@
+template <typename> class B{};
+template <typename c> class C {
+public:
+  using U = B<c>;
+};
+class A : C<A> {
+  U u;
+};