Debugging gdb'ing specific architectures [permalink] With a fat binary (32/64bit), gdb picks the 64 bit version. If you're trying to debug a 32-bit unit test on the command-line though, the 64-bitness of /Developer/Tools/otest gets in the way: % gdb /Developer/Tools/otest 2008-10-31 19:29:50.834 otest[711:813] Error loading /blah/blah/blah/build/Debug/Tests.octest/Contents/MacOS/Tests: dlopen(/bla