Support repr(C) for rustified enums #3265
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Note addition of rust-lang#3265
emilio
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Actually, if we implement the suggested check for enum class Foo : uint8_t and so, we might not even need to add this switch? We could just repr(C) by default...
I think with this patch if you have something like:
enum class Foo : uint8_t {
};Using this option will miscompile it.
At the very least we should add a big warning on this option since it'd cause wrong struct layout.
I agree this would be good. However, it appears that LLVM does not expose the necessary APIs. Even if we exposed the necessary functionality, it would presumably only work for recent clang versions. Thoughts on how to proceed? |
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It is not possible to control the repr via custom attributes so add a new rustified enum variant which does not use repr(u*) or repr(i*). Using repr(C) is sometimes necessary to bindgen enums used in functions subject to cross-language CFI checks. Closes 3263. Link: https://rcvalle.com/docs/rust-cfi-design-doc/ Signed-off-by: Per Larsen <[email protected]>
Note addition of rust-lang#3265
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TODOs:
--rustified-non-exhaustive-repr-c-enumflag?Closes #3263.