[clang] [Clang] Instantiate constexpr function when they are needed. (PR #173537)

[Erich Keane via cfe-commits]

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@@ -7064,6 +7066,27 @@ static bool handleTrivialCopy(EvalInfo &Info, const ParmVarDecl *Param,
       CopyObjectRepresentation);
 }
 
+static void InstantiateFunctionBeforeCall(const FunctionDecl *FD,
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erichkeane wrote:

There is perhaps a `try` that should be in the name of some sort.

https://github.com/llvm/llvm-project/pull/173537