[clang] [llvm] [DirectX] add Function name to DiagnosticInfoUnsupported Msg in DXILOpLowering (PR #136234)

[Justin Bogner via llvm-commits]

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@@ -139,7 +139,7 @@ class DiagnosticInfo {
 using DiagnosticHandlerFunction = std::function<void(const DiagnosticInfo &)>;
 
 class DiagnosticInfoGeneric : public DiagnosticInfo {
-  const Twine &MsgStr;
+  const Twine MsgStr;
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bogner wrote:

All of the Twine usage in Diagnostic info is super sketchy. I think we can drop this from this change and do it more comprehensively here: https://github.com/llvm/llvm-project/pull/136371

https://github.com/llvm/llvm-project/pull/136234