Bug Report Segmentation fault on Skylake/Arch Linux

[Tatsuyuki Ishi]

I'm observing segmentation fault on Linux. I have built git master from source and tried many combination of tools.

• I have tried with LIBGL_ALWAYS_SOFTWARE=1, and it yielded exactly same error.
  
• I have been running with valgrind. This crashes with null pointer (as 0x168) inside libGLX_mesa.so
  
• apitrace seems useful here. apitrace also receives a segfault if I replayed the dump. The dump is attached for analysis.

I think it should be that OBS is doing some call that doesn't work with new Mesa.

Logs:

debug: Found dbus service: org.freedesktop.ScreenSaver
Attempted path: share/obs/obs-studio/locale/en-US.ini
Attempted path: /usr/share/obs/obs-studio/locale/en-US.ini
Attempted path: share/obs/obs-studio/locale.ini
Attempted path: /usr/share/obs/obs-studio/locale.ini
Attempted path: share/obs/obs-studio/themes/Default.qss
Attempted path: /usr/share/obs/obs-studio/themes/Default.qss
Attempted path: share/obs/obs-studio/license/gplv2.txt
Attempted path: /usr/share/obs/obs-studio/license/gplv2.txt
info: Processor: 4 logical cores
info: Processor: Intel(R) Core(TM) i7-6500U CPU @ 2.50GHz
info: Physical Memory: 7732MB Total
info: Kernel Version: Linux 4.12.2-1-ARCH
info: Distribution: "Arch Linux" Unknown
debug: found alternate keycode 129 for OBS_KEY_NUMPERIOD which already has keycode 91
debug: found alternate keycode 132 for OBS_KEY_BACKSLASH which already has keycode 97
debug: found alternate keycode 218 for OBS_KEY_PRINT which already has keycode 107
info: Portable mode: false
QMetaObject::connectSlotsByName: No matching signal for on_advAudioProps_clicked()
QMetaObject::connectSlotsByName: No matching signal for on_advAudioProps_destroyed()
info: OBS 19.0.3-129-g7d1fde35 (linux)
info: ---------------------------------
info: ---------------------------------
info: audio settings reset:
    samples per sec: 44100
    speakers:        2
info: ---------------------------------
info: Initializing OpenGL...
info: OpenGL version: 4.5 (Core Profile) Mesa 17.1.5
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
debug: convert_sampler_info: 1 <= max_anisotropy <= 16 violated, selected: 0, set: 1
info: ---------------------------------
info: video settings reset:
    base resolution:   1280x720
    output resolution: 1280x720
    downscale filter:  Bicubic
    fps:               30/1
    format:            NV12
[1]    9818 segmentation fault (core dumped)  ./UI/obs

Stack trace:
#0  0x00007f85200ae2cd in  () at /usr/lib/libGLX_mesa.so.0
#1  0x00007f85302fcf63 in  () at /usr/lib/libGLX.so.0
#2  0x00007f85302fd6bd in  () at /usr/lib/libGLX.so.0
#3  0x00007f85302ff00a in  () at /usr/lib/libGLX.so.0
#4  0x00007f852057933a in device_enter_context () at /usr/lib/libobs-opengl.so.0
#5  0x00007f85417ab9d1 in gs_enter_context (graphics=0x559a630373a0)
    at ../libobs/graphics/graphics.c:271
#6  0x00007f854181a91e in render_displays () at ../libobs/obs-video.c:62
#7  0x00007f854181c0a8 in obs_video_thread (param=0x559a62e48c20) at ../libobs/obs-video.c:613
#8  0x00007f853d2d4049 in start_thread () at /usr/lib/libpthread.so.0
#9  0x00007f853d014f0f in clone () at /usr/lib/libc.so.6