If dejagnu isn't installed, make check appears to just skip over the dejagnu tests (it prints a warning), it should instead fail. Otherwize there's an apparent pass when in fact nothing was tested. This might turn out to be an automake config thing. Assign to stan initially as it affects expr.
A possible fix is something like (in common/Makefile.rules?) check-DEJAGNU: checked-for-dejagnu CLEANFILES += checked-for-dejagnu checked-for-dejagnu: <tab>$(RUNTEST) --help > /dev/null 2>&1 <tab>touch $@ see end of common/Makefile.rules for details. Might need to hang it off check-local, or might need to make it local to frysk-core?
FYI, explains why dejagnu failures were missed.
check-dejagnu is imported by automake from /usr/share/automake-X/am/dejagnu.am so I piggybacked it onto check-local