[clang] [libcxx] [Clang] Implement CWG2369 "Ordering between constraints and substitution" (PR #102857)

[Younan Zhang via cfe-commits]

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@@ -13044,6 +13045,17 @@ class Sema final : public SemaBase {
       bool SkipForSpecialization = false,
       bool ForDefaultArgumentSubstitution = false);
 
+  /// Apart from storing the result to \p Result, this behaves the same as
+  /// another overload.
+  void getTemplateInstantiationArgs(
+      MultiLevelTemplateArgumentList &Result, const NamedDecl *D,
+      const DeclContext *DC = nullptr, bool Final = false,
+      std::optional<ArrayRef<TemplateArgument>> Innermost = std::nullopt,
+      bool RelativeToPrimary = false, const FunctionDecl *Pattern = nullptr,
+      bool ForConstraintInstantiation = false,
+      bool SkipForSpecialization = false,
+      bool ForDefaultArgumentSubstitution = false);
+
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zyn0217 wrote:

This was taken from #110387, which has also been reverted due to its dependency on the refactoring work. 

The extra parameters can certainly be removed alongside the relanding of that huge patch.

https://github.com/llvm/llvm-project/pull/102857