On MacOS (ond other prefixes) glpk is keyworded while it's dependencies are not. Repoman is sad (dependency bad in 344 cases). Reproducible: Always
Missing are (at least): =sci-libs/amd-2.3.1 ** =sci-libs/colamd-2.8.0 ** =sci-libs/suitesparseconfig-4.2.1 **
I've dropped the offending keywords, sorry for the noise.