This GDB was configured as "x86_64-apple-darwin".
(gdb) attach 8679
Attaching to process 8679.
Reading symbols for shared libraries . done
Reading symbols for shared libraries ... done
0x00007fff834fb9ee in __semwait_signal ()
(gdb) handle SIGUSR2 pass nostop noprint
Signal        Stop	Print	Pass to program	Description
SIGUSR2       No	No	Yes		User defined signal 2
(gdb) c
Continuing.
Reading symbols for shared libraries ................................................................................................ done

Program received signal SIGTRAP, Trace/breakpoint trap.
[Switching to process 8679]
0x00007fff839a9790 in __CFInitialize ()
(gdb) bt full
#0  0x00007fff839a9790 in __CFInitialize ()
No symbol table info available.
#1  0x00007fff5fc0d5ce in __dyld__ZN16ImageLoaderMachO11doImageInitERKN11ImageLoader11LinkContextE ()
No symbol table info available.
#2  0x00007fff5fc0d607 in __dyld__ZN16ImageLoaderMachO16doInitializationERKN11ImageLoader11LinkContextE ()
No symbol table info available.
#3  0x00007fff5fc0bcec in __dyld__ZN11ImageLoader23recursiveInitializationERKNS_11LinkContextEj ()
No symbol table info available.
#4  0x00007fff5fc0bc9d in __dyld__ZN11ImageLoader23recursiveInitializationERKNS_11LinkContextEj ()
No symbol table info available.
#5  0x00007fff5fc0bc9d in __dyld__ZN11ImageLoader23recursiveInitializationERKNS_11LinkContextEj ()
No symbol table info available.
#6  0x00007fff5fc0bc9d in __dyld__ZN11ImageLoader23recursiveInitializationERKNS_11LinkContextEj ()
No symbol table info available.
#7  0x00007fff5fc0bda6 in __dyld__ZN11ImageLoader15runInitializersERKNS_11LinkContextE ()
No symbol table info available.
#8  0x00007fff5fc08fbb in __dyld_dlopen ()
No symbol table info available.
#9  0x00007fff834c6e00 in dlopen ()
No symbol table info available.
#10 0x000000000001cd76 in xGetSharedLibrary (path=<value temporarily unavailable, due to optimizations>, resultType=0xb029be60) at ../pmcl-kernel.c:2058
	result = (void *) 0x0
#11 0x000000000001b102 in SPffcall () at ../x86-spentry64.s:4042
No symbol table info available.
#12 0x0000000001a19aa8 in ?? ()
No symbol table info available.
#13 0x0000000001a19aa8 in ?? ()
No symbol table info available.
(gdb)