[clang] [clang] Allow C-style casts in constexpr in MS compatible mode (PR #197005)

[via cfe-commits]

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@@ -41,6 +71,7 @@ OptionalDiagnostic State::FFDiag(SourceInfo SI, diag::kind DiagId,
 
 OptionalDiagnostic State::CCEDiag(SourceLocation Loc, diag::kind DiagId,
                                   unsigned ExtraNotes) {
+  clearDiagIfNeeded(DiagId);
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eleviant wrote:

I think, we can try to skip these diagnostics instead of adding and then removing them. This seems to work better as well as removes large fraction of the code

https://github.com/llvm/llvm-project/pull/197005