Unpacking "ffmpegLinux.tar.xz" manually gives a folder
ffmpeg-4.0-64bit-static
containing the these files
-rwxr-xr-x 1 edgar users 63012968 22. Apr 21:33 ffmpeg
-rwxr-xr-x 1 edgar users 64229352 22. Apr 21:54 ffmpeg-10bit
-rwxr-xr-x 1 edgar users 62914664 22. Apr 21:33 ffprobe
-rw-r--r-- 1 edgar users 35147 22. Apr 21:54 GPLv3.txt
drwxr-xr-x 2 edgar users 4096 22. Apr 21:38 manpages
-rwxr-xr-x 1 edgar users 742480 22. Apr 21:33 qt-faststart
-rw-r--r-- 1 edgar users 2857 22. Apr 21:54 readme.txt
I used a wildcard for this folder-name in the tar-command:
QMAKE_POST_LINK += tar -C $$(HOME)/bin -xvJf FFmpeg/ffmpegLinux.tar.xz --strip=1 --wildcards */ffmpeg
Unfortunately, this wildcard seems to conflict with the dummy file "platform/qt/FFmpeg/ffmpeg". Don´t ask me, why. This is the corresponding error-message:
tar: FFmpeg/ffmpeg: Nicht im Archiv gefunden.
If I call tar with the complete archiv-path, ffmpeg is found in the archiv and gets unpacked. No more error.
QMAKE_POST_LINK += tar -C $$(HOME)/bin -xvJf FFmpeg/ffmpegLinux.tar.xz --strip=1 ffmpeg-4.0-64bit-static/ffmpeg
This fixes the normal compiling for Linux openSUSE.