[llvm] [MsgPack] Return an Error instead of bool from readFromBlob (PR #74357)

[Emma Pilkington via llvm-commits]

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@@ -5513,41 +5513,42 @@ static AMDNote getAMDNote(uint32_t NoteType, ArrayRef<uint8_t> Desc) {
 struct AMDGPUNote {
   std::string Type;
   std::string Value;
+  bool IsError;
 };
 
 template <typename ELFT>
 static AMDGPUNote getAMDGPUNote(uint32_t NoteType, ArrayRef<uint8_t> Desc) {
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epilk wrote:

This isn't really a "I'm returning either an Error or a valid AMDGPUNote" situation. In the error case, the Error object gets written into the std::string fields, I just wanted to indicate to the caller that there was an error pretty-printing so it would still dump the binary blob, which seems useful to include.

https://github.com/llvm/llvm-project/pull/74357