[clang] [Clang] Fix name lookup of conversion operators (PR #142945)

[Corentin Jabot via cfe-commits]

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@@ -3310,6 +3310,7 @@ static QualType GetDeclSpecTypeForDeclarator(TypeProcessingState &state,
       IsDeducedReturnType = true;
       break;
     case DeclaratorContext::ConversionId:
+    case DeclaratorContext::ConversionIdInPostfixExpr:
       if (!SemaRef.getLangOpts().CPlusPlus14 || !IsCXXAutoType)
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cor3ntin wrote:

Do we have tests for these diagnostics?

https://github.com/llvm/llvm-project/pull/142945