SP_SLOP 991 gc/pthread_support.c me -> backing_store_ptr = (ptr_t)GC_save_regs_in_stack() + SP_SLOP; SP_SLOP 997 gc/pthread_support.c me -> stop_info.stack_ptr += SP_SLOP; SP_SLOP 999 gc/pthread_support.c me -> stop_info.stack_ptr -= SP_SLOP;