The ebuild has several libraries in RDEPEND marked with :=, without them being in any of the other dependency lists. That doesn't make sense: fvwm3 must be rebuilt if the dependency is updated, but the dependency isn't required for building. I suspect most of the RDEPEND list should also be in DEPEND.
Indeed COMMON_DEPEND is empty in the ebuild too.
The bug has been closed via the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=2e5fd6875a959b56b5f82568a06ab1cd1f31fa14 commit 2e5fd6875a959b56b5f82568a06ab1cd1f31fa14 Author: Matt Jolly <kangie@gentoo.org> AuthorDate: 2024-12-01 02:23:40 +0000 Commit: Matt Jolly <kangie@gentoo.org> CommitDate: 2024-12-01 03:18:15 +0000 x11-wm/fvwm3: add 1.1.1, sync live This update brings the meson build sytem among other improvements! Bug: https://bugs.gentoo.org/864959 Bug: https://bugs.gentoo.org/939531 Bug: https://bugs.gentoo.org/919163 Closes: https://bugs.gentoo.org/944780 Signed-off-by: Matt Jolly <kangie@gentoo.org> x11-wm/fvwm3/Manifest | 2 + x11-wm/fvwm3/files/fvwm3-1.1.1-desk-init.patch | 32 +++++ x11-wm/fvwm3/fvwm3-1.1.1.ebuild | 185 +++++++++++++++++++++++++ x11-wm/fvwm3/fvwm3-9999.ebuild | 47 ++++--- x11-wm/fvwm3/metadata.xml | 3 - 5 files changed, 246 insertions(+), 23 deletions(-)