Not sure if this gdb-backtrace helps:
Program received signal SIGUSR1, User defined signal 1.
0x409efe78 in sigsuspend () from /lib/libc.so.6
(gdb) bt
#0 0x409efe78 in sigsuspend () from /lib/libc.so.6
#1 0x40648d44 in __pth_mctx_set () from /usr/lib/libpth.so.20
#2 0x4064c5bc in pth_spawn () from /usr/lib/libpth.so.20
#3 0x4064cdac in pth_init () from /usr/lib/libpth.so.20
#4 0x00014ddc in ?? ()
#5 0x40173e60 in ?? () from /usr/lib/libgcrypt.so.11
#6 0x4016ed78 in ?? () from /usr/lib/libgcrypt.so.11
#7 0x4016f058 in ?? () from /usr/lib/libgcrypt.so.11
#8 0x4016dc40 in gcry_control () from /usr/lib/libgcrypt.so.11
#9 0x0001618c in main ()
