Hi With 'system-webengine-webp' option you are trying to force qwebenigne to use system webp. WebEngine uses pkg-config for webp, there is no separate test, you can check it yourself with:
pkg-config --libs libwebp libwebpmux libwebpdemux Br Michal On 03/12/2018 11:07 AM, YuGiOhJCJ Mailing-List via Development wrote: > Hello, > > I am trying to build Qt 5.10.1 on Slackware64 14.2 with the > "-system-webengine-webp" option and libwebp 0.6.1: > --- > $ ./configure -v \ > [...] > -system-assimp \ > -system-doubleconversion \ > -system-freetype \ > -system-harfbuzz \ > -system-libjpeg \ > -system-libpng \ > -system-pcre \ > -system-sqlite \ > -system-xcb \ > -system-webengine-icu \ > -system-webengine-ffmpeg \ > -system-webengine-opus \ > -system-webengine-webp \ > -system-zlib \ > [...] > -pulseaudio > [...] > Note: Also available for Linux: linux-clang linux-icc > > Note: -headerdir is not a subdirectory of -prefix. > Note: -libdir is not a subdirectory of -prefix. > Note: -docdir is not a subdirectory of -prefix. > > Note: -optimized-tools is not useful in -release mode. > > Note: Dropped compiler flags '-pthread' when detecting library 'glib'. > > Note: Dropped compiler flags '-pthread' when detecting library 'gtk3'. > > Note: No wayland-egl support detected. Cross-toolkit compatibility disabled. > > Note: Dropped compiler flags '-pthread' when detecting library 'gstreamer'. > > Note: Dropped compiler flags '-pthread' when detecting library > 'gstreamer_app'. > > Note: Dropped compiler flags '-pthread' when detecting library > 'webengine-protobuf'. > > ERROR: Feature 'webengine-system-libwebp' was enabled, but the pre-condition > 'libs.webengine-webp' failed. > > ERROR: Feature 'webengine-system-ffmpeg' was enabled, but the pre-condition > 'libs.webengine-ffmpeg && features.webengine-system-opus && > features.webengine-system-libwebp' failed. > --- > > As you can see in the output above, the error is about the libwebp library > that is not found (or at least that is not working correctly). > > However, I found the test file that is checking the libwebp library and I > tried it manually: > --- > $ cd qtimageformats/config.tests/libwebp > $ qmake libwebp.pro > $ make > g++ -c -pipe -O2 -Wall -W -I/usr/lib64/qt/mkspecs/linux-g++ -I. -o libwebp.o > libwebp.cpp > libwebp.cpp: In function ‘int main(int, char**)’: > libwebp.cpp:40:20: warning: unused variable ‘output_buffer’ > [-Wunused-variable] > WebPDecBuffer *output_buffer = &config.output; > ^~~~~~~~~~~~~ > libwebp.cpp:41:28: warning: unused variable ‘bitstream’ [-Wunused-variable] > WebPBitstreamFeatures *bitstream = &config.input; > ^~~~~~~~~ > libwebp.cpp:42:17: warning: variable ‘picture’ set but not used > [-Wunused-but-set-variable] > WebPPicture picture; > ^~~~~~~ > libwebp.cpp:44:16: warning: variable ‘config2’ set but not used > [-Wunused-but-set-variable] > WebPConfig config2; > ^~~~~~~ > libwebp.cpp:47:18: warning: unused variable ‘demuxer’ [-Wunused-variable] > WebPDemuxer *demuxer = WebPDemux(&data); > ^~~~~~~ > libwebp.cpp:48:18: warning: variable ‘iter’ set but not used > [-Wunused-but-set-variable] > WebPIterator iter; > ^~~~ > --- > > So, the test file is working. > I am able to build it manually. > > Why the Qt build system is complaining about this library installed on my > system please? > > Thank you. > Best regards. > _______________________________________________ > Development mailing list > Development@qt-project.org > http://lists.qt-project.org/mailman/listinfo/development > _______________________________________________ Development mailing list Development@qt-project.org http://lists.qt-project.org/mailman/listinfo/development