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

[Younan Zhang via cfe-commits]

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@@ -1144,6 +1164,46 @@ bool Sema::CheckInstantiatedFunctionTemplateConstraints(
                                      PointOfInstantiation, Satisfaction);
 }
 
+bool Sema::CheckFunctionConstraintsWithoutInstantiation(
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zyn0217 wrote:

I moved it into CheckFunctionTemplateConstraints() - calls to e.g. SetupConstraintCheckingTemplateArgumentsAndScope() inside couldn't be reused very simply so I added another internal function to handle MLTALs.

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