root@fledgling:~ # gdb --args /usr/obj/usr/src/powerpc.powerpc64/usr.bin/clang/clang/clang.full GNU gdb (GDB) 8.2 [GDB v8.2 for FreeBSD] Copyright (C) 2018 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "powerpc64-portbld-freebsd12.0". Type "show configuration" for configuration details. For bug reporting instructions, please see: . Find the GDB manual and other documentation resources online at: . For help, type "help". Type "apropos word" to search for commands related to "word"... Reading symbols from /usr/obj/usr/src/powerpc.powerpc64/usr.bin/clang/clang/clang.full...done. (gdb) run Starting program: /usr/obj/usr/src/powerpc.powerpc64/usr.bin/clang/clang/clang.full Program received signal SIGSEGV, Segmentation fault. _tcb_ctor (thread=0x813fe4000, initial=) at /usr/src/lib/libthr/thread/thr_ctrdtr.c:47 47 tcb->tcb_thread = thread; (gdb) bt #0 _tcb_ctor (thread=0x813fe4000, initial=) at /usr/src/lib/libthr/thread/thr_ctrdtr.c:47 #1 0x00000000133b3970 in _thr_alloc (curthread=0x0) at /usr/src/lib/libthr/thread/thr_list.c:175 #2 0x00000000133b56d4 in _libpthread_init (curthread=0x0) at /usr/src/lib/libthr/thread/thr_init.c:337 #3 0x00000000133af8e8 in _thr_check_init () at /usr/src/lib/libthr/thread/thr_private.h:927 #4 __pthread_mutex_lock (mutex=0x146e8fd8 <__gthread_active_p.__gthread_active_mutex>) at /usr/src/lib/libthr/thread/thr_mutex.c:743 #5 0x00000000134387f8 in __gthread_active_p () at ./gthr-default.h:188 #6 __gthread_mutex_lock (mutex=) at ./gthr-default.h:610 #7 __register_frame_info_bases (begin=, ob=0x1468d150 , tbase=, dbase=) at /usr/src/gnu/lib/libgcc/../../../contrib/gcc/unwind-dw2-fde.c:96 #8 0x00000000100007b8 in .frame_dummy () #9 0x00000000100001f0 in ._init () #10 0x00000000100004fc in handle_static_init (argc=1, argv=, env=) at /usr/src/lib/csu/common/ignore_init.c:84 #11 0x0000000010000360 in _start (argc=, argv=, env=, obj=, cleanup=, ps_strings=) at /usr/src/lib/csu/powerpc64/crt1.c:95 (gdb)