[PATCH] D80751: [clang][diagnostics] Add '-Wundef-prefix' warning option

[Alex Lorenz via Phabricator via cfe-commits]

arphaman added a comment.

Can you still modify the state of `-Wundef` with `#pragma clang diagnostic`? Could you add a test to cover it.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D80751/new/

https://reviews.llvm.org/D80751