Incorrect code generated from inline assembly with `inout` register on riscv32im-unknown-none-elf about rust HOT 6 OPEN

Did you mean between 1.77 and 1.78? The two links look the same to me.

It looks like this has to be a regression in LLVM, which was bumped to version 18 in 1.78, because we seem to generate the exact same IR. Could you file an issue with LLVM?

https://godbolt.org/z/Te9efcnMz

Could it be that this is the same underlying issue? #126221

It looks like it, I will close that one because this one has more detail.

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I haven't looked into this too much yet, but do you know if it reproduces using C's inline assembly fed through clang? This seems like it could be an LLVM problem.

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It appears that this bug starts to appear in 1.77.

Using riscv32i-unknown-none-elf target:

1.76: https://godbolt.org/z/bKosKqvfW
1.77: https://godbolt.org/z/MYacc9na7

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Could it be that this is the same underlying issue?
#126221

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WG-prioritization assigning priority (Zulip discussion).

Being an unsound issue, maybe let's see what we can do. Compile target is Tier 2.

@rustbot label -I-prioritize +P-high

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Fix applied to LLVM 19.x llvm/llvm-project#100843

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