[clang] Basic, Sema: introduce `__attribute__((__personality__(...)))` (PR #185225)

[Erich Keane via cfe-commits]

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@@ -1655,6 +1655,15 @@ void CodeGenFunction::GenerateCode(GlobalDecl GD, llvm::Function *Fn,
 
   PGO->verifyCounterMap();
 
+  if (CurCodeDecl->hasAttr<PersonalityAttr>()) {
+    StringRef Identifier =
+        CurCodeDecl->getAttr<PersonalityAttr>()->getRoutine()->getName();
+    llvm::FunctionCallee PersonalityRoutine =
+        CGM.CreateRuntimeFunction(llvm::FunctionType::get(CGM.Int32Ty, true),
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erichkeane wrote:

This ends up being kinda problematic if we're creating this as a function, if the function already exists and we don't match function type (particularly if it would be generated after this).

I think we need to do some sort of defense here against someone defining this with what seems like a matching function, and not getting it.

Alternatively, why is this a 'return int' and 'takes variadic', rather than a stricter type?  It isn't clear form the documentation that this is what we expect out of a personality, or what we expect it to look like.

https://github.com/llvm/llvm-project/pull/185225