[PATCH] D145256: [clang/Diagnostic] Use `optional` to disambiguate between a `StoredDiagMessage` that is not set vs set as empty string

Mon Mar 6 20:50:20 PST 2023

dblaikie added a comment.

> "But when would you have a completely empty diagnostic message", you ask dear reader?
> That is when there is an empty "#warning" in code.

Is this observable from a clang command line tool? Be nice to have a lit test.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D145256/new/

https://reviews.llvm.org/D145256