Merge pull request #16068 from DougGregor/sr-7457

Author: swift-ci

lib/AST/Type.cpp

@@ -3412,7 +3412,7 @@ Type TypeBase::adjustSuperclassMemberDeclType(const ValueDecl *baseDecl,
                                    genericMemberType->getExtInfo());
   }
 
-  auto type = memberType.subst(subs);
+  auto type = memberType.subst(subs, SubstFlags::UseErrorType);
 
   if (isa<AbstractFunctionDecl>(baseDecl)) {
     type = type->replaceSelfParameterType(this);

lib/Sema/TypeCheckDecl.cpp

@@ -5334,6 +5334,7 @@ class DeclChecker : public DeclVisitor<DeclChecker> {
         // Check whether the types are identical.
         auto parentDeclTy = owningTy->adjustSuperclassMemberDeclType(
             parentDecl, decl, parentDecl->getInterfaceType());
+        if (parentDeclTy->hasError()) continue;
         parentDeclTy = parentDeclTy->getUnlabeledType(TC.Context);
         if (method) {
           // For methods, strip off the 'Self' type.

validation-test/compiler_crashers_2/0123-rdar31164540.swift renamed to validation-test/compiler_crashers_2_fixed/0123-rdar31164540.swift

@@ -1,4 +1,4 @@
-// RUN: not --crash %target-swift-frontend -parse-stdlib -DBUILDING_OUTSIDE_STDLIB %s -emit-ir
+// RUN: not %target-swift-frontend -parse-stdlib -DBUILDING_OUTSIDE_STDLIB %s -emit-ir
 // REQUIRES: objc_interop
 
 //===----------------------------------------------------------------------===//

validation-test/compiler_crashers_2_fixed/0154-sr7457.swift

@@ -0,0 +1,16 @@
+// RUN: %target-swift-frontend %s -emit-ir
+protocol Proto { }
+
+class Class {
+    func foo<A>(callback: (A) -> Void) where A: Proto {
+    }
+
+    func foo<A, B>(callback: (A, B) -> Void) where A: Proto, B: Proto {
+    }
+}
+
+class Child: Class {
+    override func foo<A>(callback: (A) -> Void) where A : Proto {
+    }
+}
+