[clang] [Clang] Implement CWG 2628 "Implicit deduction guides should propagate constraints" (PR #111143)

[Haojian Wu via cfe-commits]

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@@ -390,7 +393,7 @@ struct ConvertConstructorToDeductionGuideTransform {
               /*EvaluateConstraint=*/false);
         }
 
-        assert(NewParam->getTemplateDepth() == 0 &&
+        assert(getDepthAndIndex(NewParam).first == 0 &&
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hokein wrote:

A heads-up: we're encountering clang crashes on this assertion. I'm working on a minimal reproducer.

https://github.com/llvm/llvm-project/pull/111143