Author: arphaman Date: Wed Nov 8 13:33:15 2017 New Revision: 317727 URL: http://llvm.org/viewvc/llvm-project?rev=317727&view=rev Log: [ObjC] Boxed strings should use the nullability from stringWithUTF8String's return type
Objective-C NSString has a class method stringWithUTF8String that creates a new NSString from a C string. Objective-C box expression @(...) can be used to create an NSString instead of invoking the stringWithUTF8String method directly (The compiler lowers it down to the invocation though). This commit ensures that the type of @(string-value) gets the same nullability attributes as the return type of stringWithUTF8String to ensure that the diagnostics are consistent between the two. rdar://33847186 Differential Revision: https://reviews.llvm.org/D39762 Added: cfe/trunk/test/SemaObjC/transfer-boxed-string-nullability.m Modified: cfe/trunk/lib/Sema/SemaExprObjC.cpp Modified: cfe/trunk/lib/Sema/SemaExprObjC.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaExprObjC.cpp?rev=317727&r1=317726&r2=317727&view=diff ============================================================================== --- cfe/trunk/lib/Sema/SemaExprObjC.cpp (original) +++ cfe/trunk/lib/Sema/SemaExprObjC.cpp Wed Nov 8 13:33:15 2017 @@ -564,6 +564,13 @@ ExprResult Sema::BuildObjCBoxedExpr(Sour BoxingMethod = StringWithUTF8StringMethod; BoxedType = NSStringPointer; + // Transfer the nullability from method's return type. + Optional<NullabilityKind> Nullability = + BoxingMethod->getReturnType()->getNullability(Context); + if (Nullability) + BoxedType = Context.getAttributedType( + AttributedType::getNullabilityAttrKind(*Nullability), BoxedType, + BoxedType); } } else if (ValueType->isBuiltinType()) { // The other types we support are numeric, char and BOOL/bool. We could also Added: cfe/trunk/test/SemaObjC/transfer-boxed-string-nullability.m URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaObjC/transfer-boxed-string-nullability.m?rev=317727&view=auto ============================================================================== --- cfe/trunk/test/SemaObjC/transfer-boxed-string-nullability.m (added) +++ cfe/trunk/test/SemaObjC/transfer-boxed-string-nullability.m Wed Nov 8 13:33:15 2017 @@ -0,0 +1,28 @@ +// RUN: %clang_cc1 -fblocks -fobjc-arc -Wnullable-to-nonnull-conversion -fsyntax-only -verify -Wno-objc-root-class %s +// RUN: %clang_cc1 -fblocks -fobjc-arc -Wnullable-to-nonnull-conversion -fsyntax-only -verify -Wno-objc-root-class -DNOWARN %s + +@interface NSString + ++ (NSString* +#ifndef NOWARN + _Nullable +#else + _Nonnull +#endif +) stringWithUTF8String:(const char*)x; + +@end + +void takesNonNull(NSString * _Nonnull ptr); + +void testBoxedString() { + const char *str = "hey"; + takesNonNull([NSString stringWithUTF8String:str]); + takesNonNull(@(str)); +#ifndef NOWARN + // expected-warning@-3 {{implicit conversion from nullable pointer 'NSString * _Nullable' to non-nullable pointer type 'NSString * _Nonnull'}} + // expected-warning@-3 {{implicit conversion from nullable pointer 'NSString * _Nullable' to non-nullable pointer type 'NSString * _Nonnull'}} +#else + // expected-no-diagnostics +#endif +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
