[llvm] [llvm-profdata] Do not create numerical strings for MD5 function names read from a Sample Profile. (PR #66164)

[William Junda Huang via llvm-commits]

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@@ -80,6 +86,11 @@ namespace llvm {
     /// if (S == nullptr)
     StringRef(std::nullptr_t) = delete;
 
+    /// Disallow casting from ProfileFuncName because if it is representing a
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huangjd wrote:

Revised, now the new class no longer depends on StringRef. 

https://github.com/llvm/llvm-project/pull/66164