[clang] [clang] Implement instantiation context note for checking template parameters (PR #126088)

[Matheus Izvekov via cfe-commits]

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@@ -11802,9 +11817,10 @@ class Sema final : public SemaBase {
                                      bool PartialOrdering,
                                      bool *StrictPackMatch);
 
+  SmallString<128> toTerseString(const NamedDecl &D) const;
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mizvekov wrote:

Added comment.

The helper is still useful as it returns a string we can pass directly to diagnostic engine, versus a print overload which should operate on streams, as otherwise it would be a bit user hostile for print to mean two different things.

I believe this helper will be temporary as I will remove its other user in a future patch.

https://github.com/llvm/llvm-project/pull/126088