Index: lib/Sema/SemaDeclCXX.cpp
===================================================================
--- lib/Sema/SemaDeclCXX.cpp
+++ lib/Sema/SemaDeclCXX.cpp
@@ -9686,7 +9686,8 @@
                                                 QualType DesiredBase,
                                                 bool &AnyDependentBases) {
   // Check whether the named type is a direct base class.
-  CanQualType CanonicalDesiredBase = DesiredBase->getCanonicalTypeUnqualified();
+  CanQualType CanonicalDesiredBase = DesiredBase->getCanonicalTypeUnqualified()
+    .getUnqualifiedType();
   for (auto &Base : Derived->bases()) {
     CanQualType BaseType = Base.getType()->getCanonicalTypeUnqualified();
     if (CanonicalDesiredBase == BaseType)
Index: test/CXX/special/class.inhctor/elsewhere.cpp
===================================================================
--- test/CXX/special/class.inhctor/elsewhere.cpp
+++ test/CXX/special/class.inhctor/elsewhere.cpp
@@ -62,3 +62,4 @@
   G(int &) : G(0) {}
 };
 G<B1> g(123);
+G<const B1> g2(123);