I'm filing this report because when I run the following command:
dnf repoquery --disablerepo="*" --enablerepo="*-source" --arch=src --whatdepends flex-devel
I see xorg-x11-server listed among the results.
flex-devel used to provide only libfl.a, a static library.
As per Fedora packaging guidelines, a build dependency on a static library should be represented by depending on the -static subpackage, not the -devel one that might actually contain the static library:
https://docs.fedoraproject.org/en-US/packaging-guidelines/#_statically_linking_executables
I just changed the subpackage split of flex, and have obsoleted flex-devel.
Although build-dependent packages will continue to build, a build-dependency requiring libfl.a should now ideally build-depend on libfl-static. flex now also provides shared libraries, and a build-dependency on libfl.so, should now depend on libfl2 (shared library) and libfl2-devel (headers).