llvm / llvm/llvm-project

[Clang] No __builtin_isascii ()

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#211,821 2 comments 0 reactions 0 assignees View on GitHub

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clang:frontend extension:gnu
Dominant language
LLVM
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Description

Godbolt

int
src (int a)
{
  return __builtin_isascii (a);
}

GCC compiles this but not Clang.

Similar to LLVM bug 139946

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Reproduce the C example from the linked Godbolt case with Clang and compare its behavior with GCC. Read the related LLVM bug 139946 for context and trace Clang's handling of builtins; done means __builtin_isascii is accepted with the expected behavior and covered by a compiler test.

Written by the indexing model from the issue text.

Assessment

Tech stack
c
Domain
compilers
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Quiet
Clarity
Mostly clear
Newbie friendliness
48/100

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