[PATCH] D124726: Suggest typoed directives in preprocessor conditionals

Mon May 16 10:06:54 PDT 2022

nathanchance added subscribers: nickdesaulniers, nathanchance.
nathanchance added a comment.

I see an instance of this warning in the Linux kernel due to the "Now, for unknown directives inside a skipped conditional block, we diagnose the unknown directive as a warning if it is sufficiently similar to a directive specific to preprocessor conditional blocks" part of this change:

  arch/x86/crypto/aesni-intel_asm.S:532:8: warning: invalid preprocessing directive, did you mean '#if'? [-Wunknown-directives]
                                          # in in order to perform
                                            ^
  arch/x86/crypto/aesni-intel_asm.S:547:8: warning: invalid preprocessing directive, did you mean '#if'? [-Wunknown-directives]
                                          # in in order to perform
                                            ^
  2 warnings generated.

This is a comment within an assembler file that will be preprocessed (this is a 32-bit x86 build and the block is guarded by `#ifdef __x86_64__` on line 500):

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/x86/crypto/aesni-intel_asm.S?h=v5.18-rc7#n532

Is there anything that can be done to improve this heuristic for this case? I can try to push a patch to change the comment style for this one instance but I always worry that a warning of this nature will appear in the future and result in the kernel disabling this warning entirely.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D124726/new/

https://reviews.llvm.org/D124726