Status: Accepted Owner: stephane.ducasse Labels: Milestone-1.3 Type-Squeak New issue 3342 by stephane.ducasse: have a look at sharedQueue fixes from Levente http://code.google.com/p/pharo/issues/detail?id=3342 Check the squeak mailing: the thread of 15 of november 2010: [squeak-dev] The Trunk: Kernel-ul.515.mcz Hi Folks, Please also restore Semaphore>>critical:ifLocked: It already includes this comment: "Note: The following is tricky and depends on the fact that the VM will not switch between processes while executing byte codes (process switches happen only in real sends). The following test is written carefully so that it will result in bytecodes only." To be more explicit, in Cuis it also says: "Do not change the following #== for #=, as #== is not a real message send, just a bytecode." It's unnecessary, because #= also has it's own bytecode in the current VM. So #= won't be a real message send in this case, because both excessSignals and 0 are SmallIntegers. Also, this method has a bug. There's no guarantee, that the sender won't wait for the semaphore. I uploaded a fix to the Inbox for review recently, though I didn't get any feedback on it: http://lists.squeakfoundation.org/pipermail/squeak-dev/2010-November/155058....