[Bug modula2/125129] Many tests fail to link on FreeBSD

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125129

--- Comment #17 from ro at CeBiTec dot Uni-Bielefeld.DE <ro at CeBiTec dot Uni-Bielefeld.DE> ---
> --- Comment #16 from Gaius Mulley <gaius at gcc dot gnu.org> ---
> Closing now that the patch has been applied.

Unfortunately, that patch broke Mac OS X 10.13 bootstrap, which only has
python 2.7.16:

/vol/gcc/src/hg/master/local-slow/libgm2/configure: line 18902: no: command not
found
configure: error: Giving up

First, configure.ac calls

AC_PYTHON_DEVEL([>= '3.0'],[no],[no])

The second arg is OPTIONAL, which shouldn't be "no" since
ax_python_interpreter is used to set HAVE_PYTHON_INTERPRETER which
AFAICS *can* be false.

Unfortunately, the example in ax_python_devel.m4 contradicts the code
where an empty OPTIONAL arg means optional, while everything else means
required.

However, even if changing that, the build still fails:

configure: WARNING: this package requires Python >= '3.0'.
If you have it installed, but it isn't the default Python
interpreter in your system path, please pass the PYTHON_VERSION
variable to configure. See ``configure --help'' for reference.

configure: error: Giving up

At this point, I've given up myself ;-)