I propose to add a m4 package as a runtime dependency of flex. The m4 package used by flex in runtime. This will be useful for people who install flex from binary package, in that case DEPEND is not checked, only RDEPEND. Reproducible: Always Steps to Reproduce: # flex -oemp_ematch.lex.c emp_ematch.l # mv /usr/bin/m4 /usr/bin/m4_old # flex -oemp_ematch.lex.c emp_ematch.l flex: fatal internal error, exec failed Expected Results: .
Fixed. Thanks for the report!