[paco@blackbox ~]$ DEBUGGER=gdb steam
/home/paco/.local/share/Steam/steam.sh: line 106: VERSION_ID: unbound variable
/home/paco/.local/share/Steam/steam.sh: line 106: VERSION_ID: unbound variable
Running Steam on arch  64-bit
/home/paco/.local/share/Steam/steam.sh: line 106: VERSION_ID: unbound variable
STEAM_RUNTIME is enabled automatically
Pins up-to-date!
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Reading symbols from /home/paco/.local/share/Steam/ubuntu12_32/steam...(no debugging symbols found)...done.
LD_PRELOAD = /usr/$LIB/libstdc++.so.6 /usr/$LIB/libgcc_s.so.1 /usr/$LIB/libxcb.so.1 /usr/$LIB/libgpg-error.so
(gdb) run
Starting program: /home/paco/.local/share/Steam/ubuntu12_32/steam
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/libthread_db.so.1".
Installing breakpad exception handler for appid(steam)/version(1541819448)
[New Thread 0xf514bb40 (LWP 5219)]
Installing breakpad exception handler for appid(steam)/version(1541819448)
[New Thread 0xf4effb40 (LWP 5220)]
Installing breakpad exception handler for appid(steam)/version(1541819448)
[Detaching after fork from child process 5223]

Thread 1 "steam" received signal SIGSEGV, Segmentation fault.
0xf7a32a2d in strstr () from /usr/lib32/libc.so.6
(gdb) backtrace
#0  0xf7a32a2d in strstr () from /usr/lib32/libc.so.6
#1  0xefb35b2d in ?? () from /home/paco/.local/share/Steam/ubuntu12_32/vgui2_s.so
#2  0xefb89272 in ?? () from /home/paco/.local/share/Steam/ubuntu12_32/vgui2_s.so
#3  0xefb9add6 in ?? () from /home/paco/.local/share/Steam/ubuntu12_32/vgui2_s.so
#4  0xf365bc08 in ?? () from /home/paco/.local/share/Steam/ubuntu12_32/steamui.so
#5  0xf2c82a63 in ?? () from /home/paco/.local/share/Steam/ubuntu12_32/steamui.so
#6  0xf3167016 in ?? () from /home/paco/.local/share/Steam/ubuntu12_32/steamui.so
#7  0x5658d980 in RunSteam(int, char**, bool) ()
#8  0x5658e85b in ?? ()
#9  0x56578eec in ?? ()
#10 0xf79ccb41 in __libc_start_main () from /usr/lib32/libc.so.6
#11 0x5657c7d1 in _start ()