http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50003
Summary: -[Protocol respondsTo:] does not work with Clang Product: gcc Version: 4.6.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: libobjc AssignedTo: unassig...@gcc.gnu.org ReportedBy: nic...@gcc.gnu.org Jonathan Schleifer reports -- Hi! When using -[Protocol respondsTo:] in the new GNU runtime, it seems to return NO, even if the object conforms to the protocol. The code I use is this: + (BOOL)conformsToProtocol: (Protocol*)protocol { Class c; struct objc_protocol_list *pl; size_t i; for (c = self; c != Nil; c = class_get_super_class(c)) for (pl = c->protocols; pl != NULL; pl = pl->next) for (i = 0; i < pl->count; i++) if ([pl->list[i] conformsTo: protocol]) return YES; return NO; } It works when just using gcc 4.6.1, and it seems to work with older versions of the GNU runtime. Thanks PS: For clarity, Jonathan uses the GCC Objective-C runtime with other Objective-C compilers as well, such as clang.