while trying to reproduce bug 927276 I noticed this bug in texlive-core
Created attachment 915733 [details] texlive-core-2024-r1:20250102-090800.log texlive-core-2024-r1:20250102-090800.log
Thanks for reporting, but that is not a bug: texlive-core invokes efmtutil-sys with nonfatal. The formats will be properly generated by a mandatory later installation of a dev-texlive/* package. See also https://github.com/gentoo/gentoo/blob/c2fffae1b39cc5b3e87fec5a7d3128d448ab9f87/app-text/texlive-core/texlive-core-2024-r1.ebuild#L499-L503 The emerge process did also not fail, which may should serve as an indication that everything worked as expected.