[clang] [clang] Implement CTAD for type alias template. (PR #77890)

[via cfe-commits]

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@@ -10525,9 +10534,11 @@ class Sema final {
       SourceLocation PointOfInstantiation, FunctionDecl *Decl,
       ArrayRef<TemplateArgument> TemplateArgs,
       ConstraintSatisfaction &Satisfaction);
-  FunctionDecl *InstantiateFunctionDeclaration(FunctionTemplateDecl *FTD,
-                                               const TemplateArgumentList *Args,
-                                               SourceLocation Loc);
+  FunctionDecl *InstantiateFunctionDeclaration(
+      FunctionTemplateDecl *FTD, const TemplateArgumentList *Args,
+      SourceLocation Loc,
+      CodeSynthesisContext::SynthesisKind CSC =
+          CodeSynthesisContext::ExplicitTemplateArgumentSubstitution);
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cor3ntin wrote:

Can you explain the default value here?  If there was a default at all, one would think it would be TemplateInstantiation

https://github.com/llvm/llvm-project/pull/77890