[paco@blackbox ~]$ DEBUGGER=gdb steam-native
/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
STEAM_RUNTIME is disabled by the user
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Reading symbols from /home/paco/.local/share/Steam/ubuntu12_32/steam...(no debugging symbols found)...done.
(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(1539393410)
[New Thread 0xf529cb40 (LWP 10881)]
Installing breakpad exception handler for appid(steam)/version(1539393410)
[New Thread 0xf4fffb40 (LWP 10882)]
Installing breakpad exception handler for appid(steam)/version(1539393410)

(steam:10875): Gtk-WARNING **: 14:01:04.278: Unable to locate theme engine in module_path: "thinice",
[Detaching after fork from child process 10895]

Thread 1 "steam" received signal SIGSEGV, Segmentation fault.
0xf7a60a1d in strstr () from /usr/lib32/libc.so.6
(gdb) backtrace
#0  0xf7a60a1d in strstr () from /usr/lib32/libc.so.6
#1  0xefbfd9ed in ?? () from /home/paco/.local/share/Steam/ubuntu12_32/vgui2_s.so
#2  0xefc50d92 in ?? () from /home/paco/.local/share/Steam/ubuntu12_32/vgui2_s.so
#3  0xefc628d6 in ?? () from /home/paco/.local/share/Steam/ubuntu12_32/vgui2_s.so
#4  0xf3713ba8 in ?? () from /home/paco/.local/share/Steam/ubuntu12_32/steamui.so
#5  0xf2d61f03 in ?? () from /home/paco/.local/share/Steam/ubuntu12_32/steamui.so
#6  0xf322f4d8 in ?? () from /home/paco/.local/share/Steam/ubuntu12_32/steamui.so
#7  0x5658d8f0 in RunSteam(int, char**, bool) ()
#8  0x5658e7cb in ?? ()
#9  0x56578eac in ?? ()
#10 0xf79fab41 in __libc_start_main () from /usr/lib32/libc.so.6
#11 0x5657c741 in _start ()
(gdb) quit
A debugging session is active.

	Inferior 1 [process 10875] will be killed.

Quit anyway? (y or n) y