make install installs pip etc. with the wrong shebang

[ali-beep]

When building Python 3.10.7 from source on Linux (I have tried this using Ubuntu focal and CentOS 8 docker images), I do something like this to create a tarball distribution:

./configure --prefix=/opt/python3
make
make install DESTDIR=install
tar -C install -cJf python3.10.tar.xz opt/python3

When I extract that tarball to / the shebang for pip3, etc. is #!/opt/python3/bin/python, but that link doesn't exist.

Either make install needs to install the python symlink or the shebang should be python3 and not python.

[eli-schwartz]

This is actually a distlib bug by way of pip. distlib is used by pip to handle script creation, and it has code to detect when running from a python build build tree and use the best versioned shebang it can, but the code was broken a while ago.

I submitted a PR to distlib which should fix this, although in order to actually deploy that fix it will need to:

• be tagged in a distlib release
• get distlib updated in pip
• get a pip release
• get pip updated in CPython
• get a CPython release

So that may take a while as there are a lot of moving parts. :)