Always add `repr(C)` to rustified enums

If we don't, then eddyb's recent layout optimizations will do unexpected things
to them.

We also need to handle empty `enum`s without variants. When `repr(C)` is on a
Rust `enum`, it cannot be empty, so we need to add a dummy.

1 files changed, 15 insertions, 0 deletions

diff --git a/tests/headers/empty-enum.h b/tests/headers/empty-enum.h
new file mode 100644
index 00000000..8b7502e6
--- /dev/null
+++ b/tests/headers/empty-enum.h
@@ -0,0 +1,15 @@
+// bindgen-flags: --rustified-enum '.*Rustified.*' --constified-enum-module '.*Module.*' -- -x c++ --std=c++14
+
+// Constified is default, so no flag for that.
+
+enum EmptyConstified {};
+enum EmptyRustified {};
+enum EmptyModule {};
+
+enum class EmptyClassRustified : char {};
+enum class EmptyClassConstified : char {};
+enum class EmptyClassModule : char {};
+
+enum class ForwardClassRustified : char;
+enum class ForwardClassConstified : char;
+enum class ForwardClassModule : char;