Arch Linux User Repository

thx

Breaks with OBS Studio v31.1.2 (and possibly earlier)

Causes a segfault:

Process 37348 (obs) of user 1000 dumped core.

Stack trace of thread 37361:
#0  0x00007f8638525d3d wl_proxy_marshal_constructor (libwayland-client.so.0 + 0x6d3d)
#1  0x00007f85f4003b62 n/a (wlrobs.so + 0x3b62)
#2  0x00007f863d96a75d n/a (libobs.so.30 + 0x7475d)

OBS logs:

info: Switched to scene 'Scene'
info: ------------------------------------------------
info: Loaded scenes:
info: - scene 'Scene':
info:     - source: 'Wayland output(dmabuf)' (wlrobs-dmabuf)
info:     - source: 'Wayland output(dmabuf) 5' (wlrobs-dmabuf)
info: ------------------------------------------------
fish: Job 1, 'obs' terminated by signal SIGSEGV (Address boundary error)

Thank you for your contributions, @lilydjwg & @trinitronx.

Hi, please move wlroots from depends to makedepends. It doesn't depend on any particular wlroots once built, and some wlroots packages (e.g. wlroots0.17 in [extra]) don't provides wlroots.

This build error was a result of both -Wall (as shipped in libobs.pc pkg-config's Cflags), and setting _FORTIFY_SOURCE > 0 (which enables the warn_unused_result function attribute on ftruncate()). Arch Linux's devtools previously set it to 2 by default, but recently upgraded it to level 3 (-D_FORTIFY_SOURCE=3 in /usr/share/devtools/makepkg.conf.d/x86_64*.conf).

Upstream has pushed a fix in b8668b4d6d6d. I can verify that this now builds without the unused-result warning & error (with -Wall).

please add export CFLAGS="-Wno-error" in build() for the moment since meson setup build -Dwerror=false doesn't work

Yes, because obs-studio ships -Werror in their .pc files. The user needs to remove them to build.

However, I only occasionally get it to compile successfully according to the upstream instructions. And even if I added additional build flags(see issue), I still got the following error:

ninja: Entering directory `build'                                                                                                                                                                                                                    
[6/7] Compiling C object libwlrobs.so.p/src_scpy_source.c.o
FAILED: libwlrobs.so.p/src_scpy_source.c.o 
ccache cc -Ilibwlrobs.so.p -I. -I.. -I../inc -fdiagnostics-color=always -D_FILE_OFFSET_BITS=64 -Wall -Winvalid-pch -Wextra -O3 -DENABLE_SCPY -D_GNU_SOURCE -DENABLE_DMABUF -march=x86-64 -mtune=generic -O2 -pipe -fno-plt -fexceptions -Wp,-D_FORTIFY_SOURCE=3 -Wformat -Werror=format-security -fstack-clash-protection -fcf-protection -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer -flto=auto -fPIC -std=gnu17 -fPIC -fvisibility=hidden -fopenmp-simd -Werror -MD -MQ libwlrobs.so.p/src_scpy_source.c.o -MF libwlrobs.so.p/src_scpy_source.c.o.d -o libwlrobs.so.p/src_scpy_source.c.o -c ../src/scpy_source.c
../src/scpy_source.c: 在函数‘buffer’中:
../src/scpy_source.c:241:9: 错误：ignoring return value of ‘ftruncate’ declared with attribute ‘warn_unused_result’ [-Werror=unused-result]
  241 |         ftruncate(this->frame->fd, stride * height);
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1：所有的警告都被当作是错误
ninja: build stopped: subcommand failed.

The same compilation error also occurs in AUR wlrobs.

It doesn't seem necessary to depend wlroots at runtime?

Having a systematic segmentation fault at start after adding scpy or dmabuf in a scene (obs stable and wlrobs-hg)

Needs to uninstall hg; launch obs; delete from scene; reinstall hg; reboot obs. To get OBS working