[clang] [clang][Sema] Improve template argument deduction diagnostic (PR #122754)

[Justin Fargnoli via cfe-commits]

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@@ -777,6 +780,7 @@ clang::MakeDeductionFailureInfo(ASTContext &Context,
   case TemplateDeductionResult::IncompletePack:
     // FIXME: It's slightly wasteful to allocate two TemplateArguments for this.
   case TemplateDeductionResult::Inconsistent:
+
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justinfargnoli wrote:

```suggestion
```

https://github.com/llvm/llvm-project/pull/122754