wasm: fix ABI for enums with integer layout and ZST fields - #162826
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changes in later commits need this case out of the way
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@bors r+ Thanks for this! Perhaps at some point in the future I'd love to pick your brain on the ABI going-ons here to the extent that I want to define a new ABI for wasm where that'd be a good spot to fix all quirks we know of, but that's a conversation for a later time... |
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…excrichton wasm: fix ABI for enums with integer layout and ZST fields fixes rust-lang#121408 follow-up to rust-lang#162806 Clang is doing something that is rather annoying for us to emulate: like with unions it looks at the structure of the type, not the representation. But in rust an `enum` that is represented as an integer is not considered an `aggregate` at all, yet may still need to be passed as one if it has any (even ZST) fields. r? alexcrichton cc @hanna-kruppe
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Rollup of 7 pull requests Successful merges: - #156216 (implement const Iterator for Range) - #162748 (Enable LLVM Thin LTO for LoongArch64) - #162769 (Yeet the `DeepRegionResolver` (earlier called `OpportunisticRegionResolver`)) - #162800 (Cleanups related to RefDecodable) - #162826 (wasm: fix ABI for enums with integer layout and ZST fields) - #159359 ([rustc_public] Enhance PassMode API) - #162818 (Add regression test for malformed RPITIT bound ICE with the new solver)
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| { | ||
| // The base case: a single scalar is a singleton scalar. | ||
| if !layout.is_aggregate() { | ||
| if !(layout.is_aggregate() || layout.peel_transparent_wrappers(cx).is_enum()) { |
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I would have expected enums with data to already be considered an aggregate when #[repr] other than #[repr(Rust)] is used, even if the data is a ZST.
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Rollup of 10 pull requests Successful merges: - #156216 (implement const Iterator for Range) - #160697 (rustc: Tweak the effect of `--jobs` on frontend parallelism) - #162748 (Enable LLVM Thin LTO for LoongArch64) - #162769 (Yeet the `DeepRegionResolver` (earlier called `OpportunisticRegionResolver`)) - #162794 (Simplify `ast::UseTreeKind`) - #162800 (Cleanups related to RefDecodable) - #162826 (wasm: fix ABI for enums with integer layout and ZST fields) - #159359 ([rustc_public] Enhance PassMode API) - #162196 (Offload cmake cleanups) - #162818 (Add regression test for malformed RPITIT bound ICE with the new solver)
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Rollup merge of #162826 - folkertdev:wasm-int-enum-abi, r=alexcrichton wasm: fix ABI for enums with integer layout and ZST fields fixes #121408 follow-up to #162806 Clang is doing something that is rather annoying for us to emulate: like with unions it looks at the structure of the type, not the representation. But in rust an `enum` that is represented as an integer is not considered an `aggregate` at all, yet may still need to be passed as one if it has any (even ZST) fields. r? alexcrichton cc @hanna-kruppe
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fixes #121408
follow-up to #162806
Clang is doing something that is rather annoying for us to emulate: like with unions it looks at the structure of the type, not the representation. But in rust an
enumthat is represented as an integer is not considered anaggregateat all, yet may still need to be passed as one if it has any (even ZST) fields.r? alexcrichton
cc @hanna-kruppe