[Sema] Fix for build on some iOS programs.

Nullability attributes weren't being stripped for AttributedTypes that
were wrapped in a MacroQualifiedType. This fix adds a check for this
type and a test.

llvm-svn: 361205

clang/lib/AST/Type.cpp

@@ -3929,7 +3929,11 @@ AttributedType::getImmediateNullability() const {
 }
 
 Optional<NullabilityKind> AttributedType::stripOuterNullability(QualType &T) {
-  if (auto attributed = dyn_cast<AttributedType>(T.getTypePtr())) {
+  QualType AttrTy = T;
+  if (auto MacroTy = dyn_cast<MacroQualifiedType>(T))
+    AttrTy = MacroTy->getUnderlyingType();
+
+  if (auto attributed = dyn_cast<AttributedType>(AttrTy)) {
     if (auto nullability = attributed->getImmediateNullability()) {
       T = attributed->getModifiedType();
       return nullability;

clang/test/SemaObjC/nullability_macro.m

@@ -0,0 +1,16 @@
+// Test that nullability attributes still get merged even though they are
+// wrapped with a MacroQualifiedType. This should just compile with no errors.
+// RUN: %clang_cc1 %s -Wno-objc-root-class -fsyntax-only -verify
+#define UI_APPEARANCE_SELECTOR __attribute__((annotate("ui_appearance_selector")))
+
+@class UIColor;
+
+@interface Test
+@property(null_resettable, nonatomic, strong) UIColor *onTintColor UI_APPEARANCE_SELECTOR; // expected-warning{{treating Unicode character as whitespace}}
+@end
+
+@implementation Test
+- (void)setOnTintColor:(nullable UIColor *)onTintColor {
+}
+
+@end