On Debian Sid here with gcc-8 being the default, I have this error with the makefile:
expr: syntax error: expecting ')' instead of '6' expr: syntax error: expecting ')' instead of '1' This is because gcc -dumpversion returns only "8". It seems this is expected output, cf. https://stackoverflow.com/questions/45168516/gcc-7-1-1-on-fedora-26-dumpversion-now-only-includes-major-version-by-default So it should use -dumpfullversion -dumpversion (both, as older gcc don't know about the first option.)
