[clang] [Clang] Handle unsatisfied NestedRequirement correctly (PR #223001)

[Shafik Yaghmour via cfe-commits]

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@@ -8181,6 +8175,15 @@ Sema::BuildNestedRequirement(Expr *Constraint) {
                                   /*TemplateArgs=*/{},
                                   Constraint->getSourceRange(), Satisfaction))
     return nullptr;
+
+  if (Satisfaction.HasSubstitutionFailure()) {
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shafik wrote:

So I don't see changes to the code I pointed out, so am I to understand those changes will come as you flesh out the PR?

https://github.com/llvm/llvm-project/pull/223001