Hello!

The problem is certainly in this script or its environment, since the
only place where version can come from is this line in configure.ac:

AC_INIT([gerbv], [m4_esyscmd(utils/git-version-gen.sh 2.10.0)])

This gave me the idea to do substitution there to avoid running it.

As for wrong flag, I suggest just removing it.

Alter these changes gerbv builds and works fine for me.

Updated patch attached.