Re: [Qemu-devel] Cryptic errors from PIP install if missing openssl-devel

[Eduardo Habkost]

On Thu, Aug 29, 2019 at 11:31:25AM +1000, David Gibson wrote:
> If I attempt to run "make check-acceptance" on my POWER9, RHEL8.1
> machine when the openssl-devel package isn't installed, I get the
> following very cryptic error:
> 
>   VENV    /home/dwg/qemu/build/rhel8/tests/venv
>   PIP     /home/dwg/qemu/tests/requirements.txt
> Command "/home/dwg/qemu/build/rhel8/tests/venv/bin/python -u -c "import 
> setuptools, 
> tokenize;__file__='/tmp/pip-build-la4el5r5/cryptography/setup.py';f=getattr(tokenize,
>  'open', open)(__file__);code=f.read().replace('\r\n', 
> '\n');f.close();exec(compile(code, __file__, 'exec'))" install --record 
> /tmp/pip-1efs22iz-record/install-record.txt 
> --single-version-externally-managed --compile --install-headers 
> /home/dwg/qemu/build/rhel8/tests/venv/include/site/python3.6/cryptography" 
> failed with error code 1 in /tmp/pip-build-la4el5r5/cryptography/
> 
> Using V=1 doesn't give any more useful information, and it's not
> (easily) possible to manually re-run the given command since it relies
> on things in /tmp that are removed once the attempt finishes.

V=1 is supposed to show the actual pip command being run.  I see
it here:

  $ make check-venv V=1
  [...]
  python3 -B -m venv --system-site-packages 
/home/ehabkost/rh/proj/virt/qemu/tests/venv
* /home/ehabkost/rh/proj/virt/qemu/tests/venv/bin/python -m pip -q install -r 
/home/ehabkost/rh/proj/virt/qemu/tests/requirements.txt
  You are using pip version 19.0.3, however version 19.2.3 is available.
  You should consider upgrading via the 'pip install --upgrade pip' command.
  touch /home/ehabkost/rh/proj/virt/qemu/tests/venv

Can you reproduce the problem if you re-run the pip command?


> 
> I only figured out it was openssl-devel being missing that was the
> problem by (mostly) guesswork.  It would be really great if we could
> generate a more helpful error here.

I don't think there's much we can do about it, as the error is generated by a
package being built by pip.

There's one thing we can do to make it slightly better: not passing `-q` to pip
if running with V=1, so people can see which packages are being installed and
which one is generating the error.

> 
> In addition, if I rerun "make check-acceptance" it no longer even
> attempts the PIP install, since tests/venv already exists in my build
> environment.  It then sort of works, but I think it might be hitting
> other errors because of the missing python packages.  Sorry that's a
> bit vague - I also seem to be getting unrelated errors that I'm still
> trying to figure out.

This sounds like a bug and we need to fix it.

-- 
Eduardo