[clang] Remove delayed typo expressions (PR #143423)

[Shafik Yaghmour via cfe-commits]

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@@ -14055,8 +14055,10 @@ FunctionDecl *Sema::ResolveSingleFunctionTemplateSpecialization(
     //   specified and it, along with any default template arguments,
     //   identifies a single function template specialization, then the
     //   template-id is an lvalue for the function template specialization.
-    FunctionTemplateDecl *FunctionTemplate
-      = cast<FunctionTemplateDecl>((*I)->getUnderlyingDecl());
+    FunctionTemplateDecl *FunctionTemplate =
+        dyn_cast<FunctionTemplateDecl>((*I)->getUnderlyingDecl());
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shafik wrote:

Curious, why the change to `dyn_cast`?

https://github.com/llvm/llvm-project/pull/143423