Set the expected align for byval arguments #38870
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The alignment expected by the sysv ABI for i128 (16 bytes) does not match the alignment expected by rustc (8 bytes). Anything containing `i128`, then, when passed across the ABI boundary may result in stack/memory being trashed by the callee.
This was referenced Jan 6, 2017
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How would this have any visible effect? You seem to be setting the alignment of the type, without ever increasing it (unless I'm missing something preexisting?), and this is the default that LLVM uses anyway. |
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☔ The latest upstream changes (presumably #39095) made this pull request unmergeable. Please resolve the merge conflicts. |
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The alignment expected by the sysv ABI for i128 (16 bytes) does not match the alignment expected by
rustc (8 bytes). Anything containing
i128, then, when passed across the ABI boundary may resultin stack/memory being trashed by the callee.
Note that this does not actually fix the relevant issue, only works around it in a very specific case. Annotating alignment of byval params seems like a good idea overall anyway.
r? @eddyb