[clang] [clang-tools-extra] [clang] Extend diagnose_if to accept more detailed warning information (PR #70976)

[Björn Pettersson via cfe-commits]

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@@ -489,13 +485,7 @@ static DiagnosticIDs::Level toLevel(diag::Severity SV) {
 DiagnosticIDs::Level
 DiagnosticIDs::getDiagnosticLevel(unsigned DiagID, SourceLocation Loc,
                                   const DiagnosticsEngine &Diag) const {
-  // Handle custom diagnostics, which cannot be mapped.
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bjope wrote:

> Since this is triggering a backward incompatible behavior, can we have this bit reverted and decide how/whether we're planning to move forward with this?

Afaict the author ( @philnik777 ) has neither responded to the post-commit comments/question here, neither in the PR related to the reapply at https://github.com/llvm/llvm-project/pull/108453#issuecomment-2352155766 , and I don't know much about this to understand if there is an easy fix. But if we are suspecting "multiple bugs here" then maybe someone should just go ahead and revert this again.

Btw, it seems like the reapply already has been reverted once (https://github.com/llvm/llvm-project/commit/e1bd9740faa62c11cc785a7b70ec1ad17e286bd1) and then reapplied a second time (https://github.com/llvm/llvm-project/commit/e39205654dc11c50bd117e8ccac243a641ebd71f). And there are comments here https://github.com/llvm/llvm-project/commit/e39205654dc11c50bd117e8ccac243a641ebd71f#commitcomment-146720911 about further fixups that might cause conflicts if reverting again.

PS. The commit message in https://github.com/llvm/llvm-project/commit/e39205654dc11c50bd117e8ccac243a641ebd71f is not very informative as it says that the commit msg body says that it is a revert, while it actually is a re-apply. Maybe that is another reason to revert this mess and reapply it using a new PR with an appropriate commit message describing the feature.

https://github.com/llvm/llvm-project/pull/70976