Index: clang/lib/Sema/SemaExprObjC.cpp =================================================================== --- clang/lib/Sema/SemaExprObjC.cpp +++ clang/lib/Sema/SemaExprObjC.cpp @@ -3012,7 +3012,11 @@ << Method->getDeclName(); } - if (ReceiverType->isObjCClassType() && !isImplicit) { + // Under ARC, self can't be assigned, and doing a direct call to `self` + // when it's a Class is hence safe. For other cases, we can't trust `self` + // is what we think it is, so we reject it. + if (ReceiverType->isObjCClassType() && !isImplicit && + !(Receiver->isObjCSelfExpr() && getLangOpts().ObjCAutoRefCount)) { Diag(Receiver->getExprLoc(), diag::err_messaging_class_with_direct_method); Diag(Method->getLocation(), diag::note_direct_method_declared_at) Index: clang/test/SemaObjC/method-direct-arc.m =================================================================== --- /dev/null +++ clang/test/SemaObjC/method-direct-arc.m @@ -0,0 +1,48 @@ +// RUN: %clang_cc1 -fobjc-arc -fsyntax-only -verify -Wselector-type-mismatch %s + +extern Class object_getClass(id); + +__attribute__((objc_root_class)) +@interface Root +- (Class)class; ++ (void)directMethod __attribute__((objc_direct)); // expected-note {{direct method 'directMethod' declared here}} ++ (void)anotherDirectMethod __attribute__((objc_direct)); +@end + +@implementation Root +- (Class)class +{ + return object_getClass(self); +} ++ (void)directMethod { +} ++ (void)anotherDirectMethod { + [self directMethod]; // this should not warn +} ++ (void)regularMethod { + [self directMethod]; // this should not warn + [self anotherDirectMethod]; // this should not warn +} +- (void)regularInstanceMethod { + [[self class] directMethod]; // expected-error {{messaging a Class with a method that is possibly direct}} +} +@end + +@interface Sub : Root +@end + +@implementation Sub ++ (void)foo { + [self directMethod]; // this should not warn +} +@end + +__attribute__((objc_root_class)) +@interface Other +@end + +@implementation Other ++ (void)bar { + [self directMethod]; // expected-error {{no known class method for selector 'directMethod'}} +} +@end Index: clang/test/SemaObjC/method-direct.m =================================================================== --- clang/test/SemaObjC/method-direct.m +++ clang/test/SemaObjC/method-direct.m @@ -89,7 +89,10 @@ } - (void)otherRootDirect { } ++ (void)someRootDirectMethod { // expected-note {{direct method 'someRootDirectMethod' declared here}} +} + (void)otherClassRootDirect { + [self someRootDirectMethod]; // expected-error {{messaging a Class with a method that is possibly direct}} } - (void)rootExtensionDirect { }