This seem similar to https://bugs.gentoo.org/775659 - there appears to be a missing poppler dependency. See attached build.log Reproducible: Always
Created attachment 691026 [details] build.log
> fmtutil: running `pdftex -ini -jobname=amstex -progname=amstex -translate-file=cp227.tcx *amstex.ini' ... > pdftex: error while loading shared libraries: libpoppler.so.104: cannot open shared object file: No such file or directory I think your pdftex binary is broken and needs a rebuild. Something like $ lddtree `which pdftex` should show it in more detail. app-text/texlive-core does have a =app-text/poppler-0.87.0:= subslot depend.
> I think your pdftex binary is broken and needs a rebuild Rebuilding texlive-basic fixed it