Make file in Unix tar.gz seems to have wrong paths

[Matti V. <mav...@gm...>]

I think I previously did some modification into the .mak for this, but I
reinstalled OpenBSD, and I noticed that the problem is there still and
forgot the fix.

The problem is that by following the Unix installation guide the final line
actually produces:

gmake -f linux.mak clean test
rm -f obj/simple.*
rm -f obj/simple.obj
rm -f obj/cxxsupport.obj
rm -f obj/cxx_extensions.obj
rm -f obj/cxx_exceptions.obj
rm -f obj/cxxextensions.obj
rm -f obj/IndirectPythonInterface.obj
rm -f obj/example.*
rm -f obj/example.obj
rm -f obj/range.obj
rm -f obj/rangetest.obj
rm -f obj/pycxx_iter.*
rm -f obj/pycxx_iter.obj
Compile: Demo/Python3/simple.cxx into obj/simple.obj
g++ -c -g -Wall -fPIC -fexceptions -frtti -I. -ISrc
-I/usr/local/include/python3.10 -DNDEBUG  -oobj/simple.obj
 Demo/Python3/simple.cxx
gmake: g++: No such file or directory
gmake: *** [linux.mak:15: obj/simple.obj] Error 127

In other words, the path that the makefile seems wrong.

Is there an official fix for this?