Sema: Protocols don't have implicit members

Author: slavapestov

lib/AST/Decl.cpp

@@ -6366,6 +6366,9 @@ ConstructorDecl *NominalTypeDecl::getDefaultInitializer() const {
 }
 
 void NominalTypeDecl::synthesizeSemanticMembersIfNeeded(DeclName member) {
+  if (isa<ProtocolDecl>(this))
+    return;
+
   // Silently break cycles here because we can't be sure when and where a
   // request to synthesize will come from yet.
   // FIXME: rdar://56844567

lib/Sema/CodeSynthesis.cpp

@@ -1364,6 +1364,8 @@ evaluator::SideEffect
 ResolveImplicitMemberRequest::evaluate(Evaluator &evaluator,
                                        NominalTypeDecl *target,
                                        ImplicitMemberAction action) const {
+  ASSERT(!isa<ProtocolDecl>(target));
+
   // FIXME: This entire request is a layering violation made of smaller,
   // finickier layering violations. See rdar://56844567
 

lib/Sema/TypeCheckDecl.cpp

@@ -2941,7 +2941,7 @@ static ArrayRef<Decl *> evaluateMembersRequest(
     }
   }
 
-  if (nominal) {
+  if (nominal && !isa<ProtocolDecl>(nominal)) {
     // If the type conforms to Encodable or Decodable, even via an extension,
     // the CodingKeys enum is synthesized as a member of the type itself.
     // Force it into existence.