Disabling the WAYLIB_USE_PERCOMPILE_HEADERS option is causes compilation to fail with error: invalid use of incomplete type ‘const struct wlr_output_impl’

[daf0x]

Hi, I'm trying to compile release waylib-0.6.10_alpha and I'm running into the below error. I'm not sure how to resolve it.
I have installed qwlroots-0.5.2 and wlroots-0.18.1.

extra qwlroots configuration: -DDISABLE_WLR_PROTOCOLS=yes
extra waylib configuration: -DBUILD_TESTS=no -DDISABLE_XWAYLAND=yes -DBUILD_EXAMPLES=no -DINSTALL_TINYWL=no -DADDRESS_SANITIZER=no

I also removed the line 27 pkg_search_module(WLR_PROTOCOLS REQUIRED wlr-protocols) from server/CMakeLists.txt because I don't have that specific package and I think it's not needed. wlr-protocols is superseded by wayland-protocols is it not?

...

cmake -C /var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha_build/gentoo_common_config.cmake -G Ninja -DCMAKE_INSTALL_PREFIX=/usr -DBUILD_TESTS=no -DDISABLE_XWAYLAND=yes -DBUILD_EXAMPLES=no -DINSTALL_TINYWL=no -DADDRESS_SANITIZER=no -DCMAKE_BUILD_TYPE=RelWithDebInfo -DCMAKE_TOOLCHAIN_FILE=/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha_build/gentoo_toolchain.cmake /var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha
loading initial cache file /var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha_build/gentoo_common_config.cmake
-- The CXX compiler identification is GNU 14.2.1
-- The C compiler identification is GNU 14.2.1
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /usr/bin/x86_64-pc-linux-gnu-g++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: /usr/bin/x86_64-pc-linux-gnu-gcc - skipped
-- Detecting C compile features
-- Detecting C compile features - done
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD - Success
-- Found Threads: TRUE
-- Performing Test HAVE_STDATOMIC
-- Performing Test HAVE_STDATOMIC - Success
-- Found WrapAtomic: TRUE
-- Found OpenGL: /usr/lib64/libOpenGL.so
-- Found WrapOpenGL: TRUE
-- Found XKB: /usr/lib64/libxkbcommon.so (found suitable version "1.7.0", minimum required is "0.5.0")
-- Found WrapVulkanHeaders: /usr/include
-- Found PkgConfig: /usr/bin/x86_64-pc-linux-gnu-pkg-config (found version "2.3.0")
-- Checking for module 'wlroots-0.18=0.18.1'
--   Found wlroots-0.18, version 0.18.1
-- Checking for module 'wayland-server'
--   Found wayland-server, version 1.23.1
-- Checking for module 'pixman-1'
--   Found pixman-1, version 0.44.2
-- Checking for module 'xkbcommon'
--   Found xkbcommon, version 1.7.0
-- Checking for module 'wayland-protocols'
--   Found wayland-protocols, version 1.38
-- Create wayland protocols outputdir: /var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha_build/protocols
-- Checking for one of the modules 'libdrm'
-- Checking for one of the modules 'wayland-server'
-- Checking for one of the modules 'xcb'
-- Checking for one of the modules 'egl'

...

[11/87] /usr/bin/x86_64-pc-linux-gnu-g++ -DDISABLE_XWAYLAND -DLIBWAYLIB_SERVER_LIBRARY -DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG -DQT_NO_SIGNALS_SLOTS_KEYWORDS -DQT_OPENGL_LIB -DQT_QMLINTEGRATION_LIB -DQT_QMLMETA_LIB -DQT_QMLMODELS_LIB -DQT_QMLWORKERSCRIPT_LIB -DQT_QML_LIB -DQT_QUICK_LIB -DWLR_USE_UNSTABLE -Dwaylibserver_EXPORTS -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha_build/src/server -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha_build/src/server/waylibserver_autogen/include -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha_build/protocols -I/usr/include/qt6/QtQml/6.8.1 -I/usr/include/qt6/QtQml/6.8.1/QtQml -I/usr/include/qt6/QtCore/6.8.1 -I/usr/include/qt6/QtCore/6.8.1/QtCore -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server/kernel -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server/qtquick -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server/qtquick/private -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server/utils -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server/protocols -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server/protocols/private -I/usr/include/qt6/QtGui/6.8.1 -I/usr/include/qt6/QtGui/6.8.1/QtGui -I/usr/include/qt6/QtDBus/6.8.1 -I/usr/include/qt6/QtDBus/6.8.1/QtDBus -I/usr/include/qt6/QtQuick/6.8.1 -I/usr/include/qt6/QtQuick/6.8.1/QtQuick -I/usr/include/qt6/QtNetwork/6.8.1 -I/usr/include/qt6/QtNetwork/6.8.1/QtNetwork -I/usr/include/qt6/QtQmlMeta/6.8.1 -I/usr/include/qt6/QtQmlMeta/6.8.1/QtQmlMeta -I/usr/include/qt6/QtQmlModels/6.8.1 -I/usr/include/qt6/QtQmlModels/6.8.1/QtQmlModels -I/usr/include/qt6/QtQmlWorkerScript/6.8.1 -I/usr/include/qt6/QtQmlWorkerScript/6.8.1/QtQmlWorkerScript -I/usr/include/qt6/QtOpenGL/6.8.1 -I/usr/include/qt6/QtOpenGL/6.8.1/QtOpenGL -isystem /usr/include/qt6/QtCore -isystem /usr/include/qt6 -isystem /usr/lib64/qt6/mkspecs/linux-g++ -isystem /usr/include/qt6/QtQml -isystem /usr/include/qt6/QtQmlIntegration -isystem /usr/include/qt6/QtNetwork -isystem /usr/include/qt6/QtGui -isystem /usr/include/qt6/QtQuick -isystem /usr/include/qt6/QtQmlMeta -isystem /usr/include/qt6/QtQmlModels -isystem /usr/include/qt6/QtQmlWorkerScript -isystem /usr/include/qt6/QtOpenGL -isystem /usr/include/wlroots-0.18 -isystem /usr/include/libdrm -isystem /usr/include/pixman-1 -isystem /usr/include/elogind -isystem /usr/lib64/libffi/include -isystem /usr/include/qwlroots  -march=core2 -msse4.1 -mxsave --param=l1-cache-line-size=64 --param=l1-cache-size=32 --param=l2-cache-size=6144 -O2 -pipe -fno-semantic-interposition -mfpmath=sse      -flto           -Werror=odr     -Werror=lto-type-mismatch        -Werror=strict-aliasing         -fgcse-after-reload     -floop-interchange      -fpeel-loops    -fpredictive-commoning  -ftree-partial-pre      -floop-block    -fgraphite-identity -std=gnu++20 -fPIC -fPIC -MD -MT src/server/CMakeFiles/waylibserver.dir/kernel/woutput.cpp.o -MF src/server/CMakeFiles/waylibserver.dir/kernel/woutput.cpp.o.d -o src/server/CMakeFiles/waylibserver.dir/kernel/woutput.cpp.o -c /var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server/kernel/woutput.cpp
FAILED: src/server/CMakeFiles/waylibserver.dir/kernel/woutput.cpp.o
/usr/bin/x86_64-pc-linux-gnu-g++ -DDISABLE_XWAYLAND -DLIBWAYLIB_SERVER_LIBRARY -DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG -DQT_NO_SIGNALS_SLOTS_KEYWORDS -DQT_OPENGL_LIB -DQT_QMLINTEGRATION_LIB -DQT_QMLMETA_LIB -DQT_QMLMODELS_LIB -DQT_QMLWORKERSCRIPT_LIB -DQT_QML_LIB -DQT_QUICK_LIB -DWLR_USE_UNSTABLE -Dwaylibserver_EXPORTS -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha_build/src/server -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha_build/src/server/waylibserver_autogen/include -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha_build/protocols -I/usr/include/qt6/QtQml/6.8.1 -I/usr/include/qt6/QtQml/6.8.1/QtQml -I/usr/include/qt6/QtCore/6.8.1 -I/usr/include/qt6/QtCore/6.8.1/QtCore -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server/kernel -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server/qtquick -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server/qtquick/private -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server/utils -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server/protocols -I/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server/protocols/private -I/usr/include/qt6/QtGui/6.8.1 -I/usr/include/qt6/QtGui/6.8.1/QtGui -I/usr/include/qt6/QtDBus/6.8.1 -I/usr/include/qt6/QtDBus/6.8.1/QtDBus -I/usr/include/qt6/QtQuick/6.8.1 -I/usr/include/qt6/QtQuick/6.8.1/QtQuick -I/usr/include/qt6/QtNetwork/6.8.1 -I/usr/include/qt6/QtNetwork/6.8.1/QtNetwork -I/usr/include/qt6/QtQmlMeta/6.8.1 -I/usr/include/qt6/QtQmlMeta/6.8.1/QtQmlMeta -I/usr/include/qt6/QtQmlModels/6.8.1 -I/usr/include/qt6/QtQmlModels/6.8.1/QtQmlModels -I/usr/include/qt6/QtQmlWorkerScript/6.8.1 -I/usr/include/qt6/QtQmlWorkerScript/6.8.1/QtQmlWorkerScript -I/usr/include/qt6/QtOpenGL/6.8.1 -I/usr/include/qt6/QtOpenGL/6.8.1/QtOpenGL -isystem /usr/include/qt6/QtCore -isystem /usr/include/qt6 -isystem /usr/lib64/qt6/mkspecs/linux-g++ -isystem /usr/include/qt6/QtQml -isystem /usr/include/qt6/QtQmlIntegration -isystem /usr/include/qt6/QtNetwork -isystem /usr/include/qt6/QtGui -isystem /usr/include/qt6/QtQuick -isystem /usr/include/qt6/QtQmlMeta -isystem /usr/include/qt6/QtQmlModels -isystem /usr/include/qt6/QtQmlWorkerScript -isystem /usr/include/qt6/QtOpenGL -isystem /usr/include/wlroots-0.18 -isystem /usr/include/libdrm -isystem /usr/include/pixman-1 -isystem /usr/include/elogind -isystem /usr/lib64/libffi/include -isystem /usr/include/qwlroots  -march=core2 -msse4.1 -mxsave --param=l1-cache-line-size=64 --param=l1-cache-size=32 --param=l2-cache-size=6144 -O2 -pipe -fno-semantic-interposition -mfpmath=sse      -flto           -Werror=odr     -Werror=lto-type-mismatch       -Werror=strict-aliasing          -fgcse-after-reload     -floop-interchange      -fpeel-loops    -fpredictive-commoning  -ftree-partial-pre      -floop-block    -fgraphite-identity -std=gnu++20 -fPIC -fPIC -MD -MT src/server/CMakeFiles/waylibserver.dir/kernel/woutput.cpp.o -MF src/server/CMakeFiles/waylibserver.dir/kernel/woutput.cpp.o.d -o src/server/CMakeFiles/waylibserver.dir/kernel/woutput.cpp.o -c /var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server/kernel/woutput.cpp
/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server/kernel/woutput.cpp: In function ‘bool Waylib::Server::output_pick_cursor_format(wlr_output*, wlr_drm_format*, uint32_t)’:
/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server/kernel/woutput.cpp:385:21: error: invalid use of incomplete type ‘const struct wlr_output_impl’
  385 |     if (output->impl->get_cursor_formats) {
      |                     ^~
In file included from /usr/include/qwlroots/qwoutput.h:11,
                 from /var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server/kernel/woutput.h:8,
                 from /var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server/kernel/woutput.cpp:4:
/usr/include/wlroots-0.18/wlr/types/wlr_output.h:114:8: note: forward declaration of ‘struct wlr_output_impl’
  114 | struct wlr_output_impl;
      |        ^~~~~~~~~~~~~~~
/var/tmp/portage/dev-libs/waylib-0.6.10_alpha/work/waylib-0.6.10-alpha/src/server/kernel/woutput.cpp:387:25: error: invalid use of incomplete type ‘const struct wlr_output_impl’
  387 |             output->impl->get_cursor_formats(output, allocator->buffer_caps);
      |                         ^~
/usr/include/wlroots-0.18/wlr/types/wlr_output.h:114:8: note: forward declaration of ‘struct wlr_output_impl’
  114 | struct wlr_output_impl;
      |        ^~~~~~~~~~~~~~~
ninja: build stopped: subcommand failed.

Looking for the definition of struct wlr_output_impl:

$ grep -r wlr_output_impl /usr/include/*wlroots*/
/usr/include/wlroots-0.18/wlr/types/wlr_output.h:struct wlr_output_impl;
/usr/include/wlroots-0.18/wlr/types/wlr_output.h:       const struct wlr_output_impl *impl;
/usr/include/wlroots-0.18/wlr/interfaces/wlr_output.h:struct wlr_output_impl {
/usr/include/wlroots-0.18/wlr/interfaces/wlr_output.h:  const struct wlr_output_impl *impl, struct wl_event_loop *event_loop,

struct wlr_output_impl is defined in wlr/interfaces/wlr_output.h, but I can't see an include path from waylib-0.6.10-alpha/src/server/kernel/woutput.cpp to that file. Via types/qwoutput.h in qwlroots only <wlr/types/wlr_output.h> appears to be included, not <wlr/interfaces/wlr_output.h>?

I'm not sure what information is useful to include, please let me know if anything is needed.

[daf0x]

I figured out the problem. The issue is that without pre-compiled headers this package does not compile. At least the following files are missing #include directives that are exclusively found in pch/pch.hxx:

• src/server/kernel/woutput.cpp
• src/server/kernel/wsurface.cpp
• src/server/kernel/woutputlayout.cpp
• src/server/qtquick/woutputrenderwindow.cpp
• src/server/qtquick/wquickoutputlayout.cpp
• src/server/qtquick/wrenderhelper.cpp
• src/server/qtquick/wsgtextureprovider.cpp
• src/server/utils/wtools.cpp
• src/server/utils/wimagebuffer.cpp
• src/server/protocols/wxdgpopupsurface.cpp
• src/server/protocols/wxdgtoplevelsurface.cpp
• src/server/protocols/wxwaylandsurface.cpp
• src/server/protocols/winputpopupsurface.cpp

This means that the WAYLIB_USE_PERCOMPILE_HEADERS option is currently broken.

Common best practice when using pre-compiled headers in a project is to enable them only for developers, to speed up compilation during development. However, when building a release or CI build pre-compiled headers should NOT be used. This approach allows developers to enjoy faster builds while ensuring that CI builds remain consistent and reproducible.

Even with WAYLIB_USE_PERCOMPILE_HEADERS=on ninja did not seem to want to generate or use the pre-compiled header. I am not sure how or if it's related, but please do note that the default stance of Gentoo appears to be to not support pre-compiled headers: https://github.com/gentoo/gentoo/blob/12d10fba7c53fa06425b3c28d347ecd8ce35a55b/profiles/base/use.mask#L55 .

[wineee]

It should be noted that wlr-protocols is still required, and it's source code is in https://gitlab.freedesktop.org/wlroots/wlr-protocols. wlr-protocols is an extended set of wayland-protocols, which contains many protocols that are very useful for treeland, such as layer-shell, output-management.