Revision: 5234 http://trac.macosforge.org/projects/ruby/changeset/5234 Author: lsansonetti@apple.com Date: 2011-02-18 15:15:30 -0800 (Fri, 18 Feb 2011) Log Message: ----------- fix a race condition bug when dispatching and resolving a method at the same time Modified Paths: -------------- MacRuby/trunk/dispatcher.cpp Modified: MacRuby/trunk/dispatcher.cpp =================================================================== --- MacRuby/trunk/dispatcher.cpp 2011-02-18 23:14:44 UTC (rev 5233) +++ MacRuby/trunk/dispatcher.cpp 2011-02-18 23:15:30 UTC (rev 5234) @@ -673,13 +673,26 @@ // Does the receiver implements -forwardInvocation:? if ((opt & DISPATCH_SUPER) == 0 && rb_objc_supports_forwarding(self, sel)) { + +#if MAC_OS_X_VERSION_MAX_ALLOWED < 1070 + // In earlier versions of the Objective-C runtime, there seems + // to be a bug where class_getInstanceMethod isn't atomic, + // and might return NULL while at the exact same time another + // thread registers the related method. + // As a work-around, we double-check if the method still does + // not exist here. If he does, we can dispatch it properly. + method = class_getInstanceMethod(klass, sel); + if (method != NULL) { + goto recache2; + } +#endif fill_ocache(cache, self, klass, (IMP)objc_msgSend, sel, NULL, argc); goto dispatch; } // Let's see if are not trying to call a Ruby method that accepts - // a regular argument then a optional Hash argument, to be + // a regular argument then an optional Hash argument, to be // compatible with the Ruby specification. const char *selname = (const char *)sel; size_t selname_len = strlen(selname);