It's a known bug that gdb (I've tried up to 5.0) fails when debugging any executable that includes pthreads under Irix 6.5 (fails with unknown signal message and locks up). I tried mapping the various signals, but could not get it to work. Has anyone got a fix in the works? Does anyone have any ideas of how to debug g++ code on an Irix machine that uses threads short of lots of print statements? Any help will be greatly appreciated. Charles