Arch Linux User Repository

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

It looks like this compiles fine with the obs-studio package again, no need for obs-studio-git anymore. This finally includes wayland preview support.

Note: Since commit 5f1c794e4614, you need to build this against an obs-studio with commit 7867d16, which while I was writing this isn't available in the [community]'s 26.1.2-1. So build it against obs-studio-git for now.

If the obs preview is transparent (showing the desktop / whatever window is behind it), obs can either be run on XWayland with QT_QPA_PLATFORM=xcb or with proper Wayland support which is being worked on here https://github.com/obsproject/obs-studio/pull/2484
The AUR package obs-studio-wayland contains all these patches.

The screencopy backend works with default obs, however for dmabuf OBS needs EGL support. The linked PR above for Wayland support also makes EGL work, so that is probably the best way to use this.