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This would presumably cause __malloc_lock() to >> fail, but there's no error check. > > That sounds more likely. In theory this shouldn't have much influence, > though. First of all, all fixup calls are running in a single thread, > so there's no serialization required(*), and the malloc_init call > doesn't set up the malloc arena, it just initializes the muto and checks > for user space provided malloc calls, which is not a problem in this > scenario. > > (*) unless multiple threads are started during fixup and some of these > threads mallocate memory again... > > Ken, is there a chance to tweak the fifo code to stop creating > threads from inside fixup, and to defer the thread start to the first > call in the process actually relying on the thread being started? I can't think of any way to do that. The thread is listening for various events that cause it to take action, so it has to always be running. But I can probably tweak the code so that the thread doesn't have to call malloc early on. It might take a while to get this right, and the bug has existed ever since I overhauled the fifo code. So I don't think you have to hold up releasing 3.3.0 while I work on this. Ken