[libcxx-commits] [clang] [libcxx] [Clang][WIP] Normalize constraints before checking for satisfaction (PR #141776)

[Younan Zhang via libcxx-commits]

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@@ -1631,20 +2143,23 @@ NormalizedConstraint::fromConstraintExpr(Sema &S, const NamedDecl *D,
       // constraint. If any such substitution results in an invalid type or
       // expression, the program is ill-formed; no diagnostic is required.
       // [...]
-      ConceptDecl *CD = CSE->getNamedConcept();
-      SubNF = S.getNormalizedAssociatedConstraints(
-          CD, AssociatedConstraint(CD->getConstraintExpr()));
+
+      // Use canonical declarations to merge ConceptDecls across
+      // different modules.
+      ConceptDecl *CD = CSE->getNamedConcept()->getCanonicalDecl();
+      SubNF = NormalizedConstraint::fromAssociatedConstraints(
+          S, CD, AssociatedConstraint(CD->getConstraintExpr(), SubstIndex));
+
       if (!SubNF)
-        return std::nullopt;
+        return nullptr;
     }
+    // if (substituteParameterMappings(S, *SubNF, CSE))
+    //   return nullptr;
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zyn0217 wrote:

leftovers

https://github.com/llvm/llvm-project/pull/141776