pip install fails on FreeBSD (clang)

[mike-pt]

Exception information:
Traceback (most recent call last):
File "/usr/local/lib/python2.7/site-packages/pip/basecommand.py", line 122, in main
status = self.run(options, args)
File "/usr/local/lib/python2.7/site-packages/pip/commands/install.py", line 283, in run
requirement_set.install(install_options, global_options, root=options.root_path)
File "/usr/local/lib/python2.7/site-packages/pip/req.py", line 1435, in install
requirement.install(install_options, global_options, _args, *_kwargs)
File "/usr/local/lib/python2.7/site-packages/pip/req.py", line 706, in install
cwd=self.source_dir, filter_stdout=self._filter_install, show_stdout=False)
File "/usr/local/lib/python2.7/site-packages/pip/util.py", line 697, in call_subprocess
% (command_desc, proc.returncode, cwd))
InstallationError: Command /usr/local/bin/python2.7 -c "import setuptools, tokenize;file='/tmp/pip_build_root/libsass/setup.py';exec(compile(getattr(tokenize, 'open', open)(file).read().replace('\r\n', '\n'), file, 'exec'))" install --record /tmp/pip-sWz80n-record/install-record.txt --single-version-externally-managed --compile failed with error code 1 in /tmp/pip_build_root/libsass

[mike-pt]

Forgot to past the ouput:
cc -fno-strict-aliasing -O2 -pipe -fno-strict-aliasing -DNDEBUG -fPIC -I./libsass -I/usr/local/include/python2.7 -c libsass/cencode.c -o build/temp.freebsd-11.0-CURRENT-amd64-2.7/libsass/cencode.o -c -O2 -fPIC -std=c++0x -Wall -Wno-parentheses

error: invalid argument '-std=c++0x' not allowed with 'C/ObjC'

error: command 'cc' failed with exit status 1

---

Cleaning up...
Command /usr/local/bin/python2.7 -c "import setuptools, tokenize;file='/tmp/pip_build_root/libsass/setup.py';exec(compile(getattr(tokenize, 'open', open)(file).read().replace('\r\n', '\n'), file, 'exec'))" install --record /tmp/pip-dWhyv8-record/install-record.txt --single-version-externally-managed --compile failed with error code 1 in /tmp/pip_build_root/libsass
Storing debug log for failure in /home/user/.pip/pip.log

[gasman]

What version of clang are you using? According to https://github.com/dahlia/libsass-python it needs to be 2.9 or above.

[mike-pt]

it's 3.4.1 clang is the default compiler in freebsd 10+++

I've never seen this -std=c++0x.... wonder where it comes from....

[gasman]

Apparently "c++0x" was the name for the "c++11" standard when it was in development, so perhaps newer versions of clang have dropped the old name...

In any case, this problem here is within the libsass-python library, or - more likely - libsass itself. (django-libsass is just a wrapper for those projects, and does not deal with the C++ code directly.) You'll need to try building libsass on its own, and see if you get the same error... if so, you should raise this as a bug in that project.

[prydie]

We've come up against a similar issue previously with node-sass on FreeBSD. The easiest workaround is to install gcc and set CC and CXX when running pip install -r requirements.txt. Though I agree with @gasman that the issue should be fixed upstream.

Example:

CXX=g++ CC=gcc48 /home/vagrant/app/env/bin/pip install -r /home/vagrant/app/requirements.txt