[clang] [Clang] prevent constexpr crash on invalid overrides (PR #184048)

[Shafik Yaghmour via cfe-commits]

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@@ -9247,9 +9247,12 @@ bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) {
         continue;
       if (Overridden.insert(BaseMD).second) {
         MD->addOverriddenMethod(BaseMD);
-        CheckOverridingFunctionReturnType(MD, BaseMD);
-        CheckOverridingFunctionAttributes(MD, BaseMD);
-        CheckOverridingFunctionExceptionSpec(MD, BaseMD);
+        bool Invalid = false;
+        Invalid |= CheckOverridingFunctionReturnType(MD, BaseMD);
+        Invalid |= CheckOverridingFunctionAttributes(MD, BaseMD);
+        Invalid |= CheckOverridingFunctionExceptionSpec(MD, BaseMD);
+        if (Invalid)
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shafik wrote:

This was not meant to be blocking, I think we can merge this. Maybe leave a comment this is an open question.

https://github.com/llvm/llvm-project/pull/184048