Le Tue, Nov 11, 2025 at 05:16:48PM +1100, Jonathan Gray a écrit :
> On Sat, Nov 01, 2025 at 06:33:19PM +0100, Landry Breuil wrote:
> > hi,
> > 
> > currently mesa isnt built with wayland support (which is a topic in itself).
> > When running on wayland, starting any gtk+4 app will crash early when
> > initializing, because we end up taking a libxcb codepath, eg run gtk+4-demo:
> > 
> > Program terminated with signal SIGSEGV, Segmentation fault.
> > #0  0x00000316d2ae48aa in XGetXCBConnection () from /usr/X11R6/lib/libX11-xcb.so.2.0
> > [Current thread is 1 (process 381892)]
> > (gdb) bt
> > #0  0x00000316d2ae48aa in XGetXCBConnection () from /usr/X11R6/lib/libX11-xcb.so.2.0
> > #1  0x00000316849f7ff4 in dri2_get_xcb_connection (disp=0x31632dbc5a0, dri2_dpy=0x3161541bcc0) at /usr/xenocara/lib/mesa/mk/libEGL/../../src/egl/drivers/dri2/platform_x11.c:1720
> > #2  0x00000316849f7ad8 in dri2_initialize_x11_dri3 (disp=0x31632dbc5a0) at /usr/xenocara/lib/mesa/mk/libEGL/../../src/egl/drivers/dri2/platform_x11.c:1926
> > #3  dri2_initialize_x11 (disp=0x31632dbc5a0) at /usr/xenocara/lib/mesa/mk/libEGL/../../src/egl/drivers/dri2/platform_x11.c:2095
> > #4  0x00000316849e3ee5 in dri2_initialize (disp=0x31632dbc5a0) at /usr/xenocara/lib/mesa/mk/libEGL/../../src/egl/drivers/dri2/egl_dri2.c:891
> > #5  0x00000316849e79b1 in eglInitialize (dpy=<optimized out>, major=0x7eac247c3468, minor=0x7eac247c346c) at /usr/xenocara/lib/mesa/mk/libEGL/../../src/egl/main/eglapi.c:705
> > #6  0x000003163bf7675e in gdk_display_init_egl () from /usr/local/lib/libgtk-4.so.5.5
> > #7  0x000003163bf0c073 in gdk_wayland_display_init_gl () from /usr/local/lib/libgtk-4.so.5.5
> > #8  0x000003163bf76399 in gdk_display_prepare_gl () from /usr/local/lib/libgtk-4.so.5.5
> > #9  0x000003163bfe1217 in get_renderer_for_gl () from /usr/local/lib/libgtk-4.so.5.5
> > #10 0x000003163bfe0880 in gsk_renderer_new_for_surface_full () from /usr/local/lib/libgtk-4.so.5.5
> > #11 0x000003163bd2b543 in gtk_window_realize () from /usr/local/lib/libgtk-4.so.5.5
> > 
> > it can also be seen with /usr/local/lib/firefox/glxtest -w, which also calls
> > eglIinitialize:
> > https://searchfox.org/firefox-main/source/toolkit/xre/glxtest/glxtest.cpp#612
> > 
> > looking at the code, display->Platform is X11, since wayland support isnt
> > builtin:
> > 
> > #4  0x00000316849e3ee5 in dri2_initialize (disp=0x31632dbc5a0) at /usr/xenocara/lib/mesa/mk/libEGL/../../src/egl/drivers/dri2/egl_dri2.c:891
> > (gdb) p disp->Platform
> > $3 = _EGL_PLATFORM_X11
> > 
> > so, i think we should fail early if we know we're on wayland. maybe the test
> > should be !!getenv(DISPLAY) to negate the condition, but i've stolen it from
> > https://github.com/openbsd/xenocara/blob/master/lib/mesa/src/vulkan/device-select-layer/device_select_layer.c#L149
> > and in my limited testing, now i can run gtk4-demo or d-spy from within wayland,
> > and glxtest doesnt crash when firefox starts:
> > 
> > $/usr/local/lib/firefox/glxtest
> > WARNING
> > libEGL initialize failed
> > VENDOR
> > AMD
> > RENDERER
> > AMD Radeon Vega 10 Graphics (radeonsi, raven, ACO, DRM 3.61, 7.8)
> > VERSION
> > 4.6 (Compatibility Profile) Mesa 25.0.7
> > TFP
> > TRUE
> > MESA_VENDOR_ID
> > 0x1002
> > MESA_DEVICE_ID
> > 0x15d8
> > MESA_ACCELERATED
> > TRUE
> > MESA_VRAM
> > 2048MB
> > DRI_DRIVER
> > radeonsi
> > TEST_TYPE
> > GLX
> > 
> > $/usr/local/lib/firefox/glxtest -w
> > WARNING
> > libEGL initialize failed
> > ERROR
> > EGL test failed
> > TEST_TYPE
> > EGL
> > 
> > so, how about the following diff, for now ?
> > 
> > Landry
> 
> How about this instead?  Works with glxtest -w running on wayland.

gives the same result for me, gtk4-demo doesnt crash, nor does glxtest
-w. feels more correct anyway.. ok for me.

$/usr/local/lib/firefox/glxtest -w
WARNING
libEGL initialize failed
ERROR
EGL test failed
TEST_TYPE
EGL