Hi haziran. Please make a new issue in the GitHub tracker. See https://github.com/Framstag/libosmscout/issues Please also make sure that you use the current code in the GitHub repository. The source version here at Sourceforge is old. Possibly your issue is resolved after this. I also recommend taking a look at he GitHub automatic builds, especially https://github.com/Framstag/libosmscout/blob/master/.github/workflows/build_and%20test_on_vs2019.yml that show a possible build for cmake+vcpkg or alternatively...
Merge branch 'master' of https://github.com/Framstag/libosmscout
Bugfixes and improved cmake build for map library.
Bugfixes and improved cmake build for core library.
Improved qt client library cmake build.
Remove even more clang-tidy warnings.
Fixed build.
Simplified cmake files target handling for libosmscoutmapsvg and libosmsocutmapopengl. Let's see if LIBRARY_OUTPUT_NAME works.