psycopg2cffi does not build on Python 3.7

[stefankoegl]

It seems that psycopg2cffi does not build on the upcoming Python 3.7. My tests are failing with the following error.

Collecting psycopg2cffi==2.7.7 (from -r requirements.txt (line 13))
  Downloading psycopg2cffi-2.7.7.tar.gz (62kB)
    100% |████████████████████████████████| 71kB 8.3MB/s 
    Complete output from command python setup.py egg_info:
    c/_cffi_backend.c: In function ‘b_cast’:
    c/_cffi_backend.c:3903:37: warning: ‘value’ may be used uninitialized in this function [-Wmaybe-uninitialized]
                     write_raw_float_data(cd->c_data, value, ct->ct_size);
                                         ^
    c/_cffi_backend.c:3859:16: note: ‘value’ was declared here
             double value;
                    ^
    c/ffi_obj.c: In function ‘ffi_cast’:
    c/_cffi_backend.c:3903:37: warning: ‘value’ may be used uninitialized in this function [-Wmaybe-uninitialized]
                     write_raw_float_data(cd->c_data, value, ct->ct_size);
                                         ^
    c/_cffi_backend.c:3859:16: note: ‘value’ was declared here
             double value;
                    ^
    
    Installed /tmp/pip-build-v2tv6uqy/psycopg2cffi/.eggs/cffi-1.11.4-py3.7-linux-x86_64.egg
    Searching for pycparser
    Reading https://pypi.python.org/simple/pycparser/
    Downloading https://pypi.python.org/packages/8c/2d/aad7f16146f4197a11f8e91fb81df177adcc2073d36a17b1491fd09df6ed/pycparser-2.18.tar.gz#md5=72370da54358202a60130e223d488136
    Best match: pycparser 2.18
    Processing pycparser-2.18.tar.gz
    Writing /tmp/easy_install-8ftkx85p/pycparser-2.18/setup.cfg
    Running pycparser-2.18/setup.py -q bdist_egg --dist-dir /tmp/easy_install-8ftkx85p/pycparser-2.18/egg-dist-tmp-1ug68gco
    warning: no previously-included files matching 'yacctab.*' found under directory 'tests'
    warning: no previously-included files matching 'lextab.*' found under directory 'tests'
    warning: no previously-included files matching 'yacctab.*' found under directory 'examples'
    warning: no previously-included files matching 'lextab.*' found under directory 'examples'
    zip_safe flag not set; analyzing archive contents...
    Traceback (most recent call last):
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/sandbox.py", line 154, in save_modules
        yield saved
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/sandbox.py", line 195, in setup_context
        yield
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/sandbox.py", line 250, in run_setup
        _execfile(setup_script, ns)
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/sandbox.py", line 45, in _execfile
        exec(code, globals, locals)
      File "/tmp/easy_install-8ftkx85p/pycparser-2.18/setup.py", line 54, in <module>
        'Topic :: Database :: Front-Ends',
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/__init__.py", line 129, in setup
        return distutils.core.setup(**attrs)
      File "/opt/python/3.7-dev/lib/python3.7/distutils/core.py", line 148, in setup
        dist.run_commands()
      File "/opt/python/3.7-dev/lib/python3.7/distutils/dist.py", line 966, in run_commands
        self.run_command(cmd)
      File "/opt/python/3.7-dev/lib/python3.7/distutils/dist.py", line 985, in run_command
        cmd_obj.run()
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/command/bdist_egg.py", line 218, in run
        os.path.join(archive_root, 'EGG-INFO'), self.zip_safe()
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/command/bdist_egg.py", line 269, in zip_safe
        return analyze_egg(self.bdist_dir, self.stubs)
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/command/bdist_egg.py", line 379, in analyze_egg
        safe = scan_module(egg_dir, base, name, stubs) and safe
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/command/bdist_egg.py", line 416, in scan_module
        code = marshal.load(f)
    ValueError: bad marshal data (unknown type code)
    
    During handling of the above exception, another exception occurred:
    
    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/tmp/pip-build-v2tv6uqy/psycopg2cffi/setup.py", line 126, in <module>
        setup(**setup_kwargs)
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/__init__.py", line 128, in setup
        _install_setup_requires(attrs)
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/__init__.py", line 123, in _install_setup_requires
        dist.fetch_build_eggs(dist.setup_requires)
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/dist.py", line 461, in fetch_build_eggs
        replace_conflicting=True,
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/pkg_resources/__init__.py", line 866, in resolve
        replace_conflicting=replace_conflicting
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/pkg_resources/__init__.py", line 1146, in best_match
        return self.obtain(req, installer)
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/pkg_resources/__init__.py", line 1158, in obtain
        return installer(requirement)
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/dist.py", line 528, in fetch_build_egg
        return cmd.easy_install(req)
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/command/easy_install.py", line 673, in easy_install
        return self.install_item(spec, dist.location, tmpdir, deps)
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/command/easy_install.py", line 699, in install_item
        dists = self.install_eggs(spec, download, tmpdir)
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/command/easy_install.py", line 882, in install_eggs
        return self.build_and_install(setup_script, setup_base)
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/command/easy_install.py", line 1150, in build_and_install
        self.run_setup(setup_script, setup_base, args)
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/command/easy_install.py", line 1136, in run_setup
        run_setup(setup_script, args)
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/sandbox.py", line 253, in run_setup
        raise
      File "/opt/python/3.7-dev/lib/python3.7/contextlib.py", line 127, in __exit__
        self.gen.throw(type, value, traceback)
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/sandbox.py", line 195, in setup_context
        yield
      File "/opt/python/3.7-dev/lib/python3.7/contextlib.py", line 127, in __exit__
        self.gen.throw(type, value, traceback)
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/sandbox.py", line 166, in save_modules
        saved_exc.resume()
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/sandbox.py", line 141, in resume
        six.reraise(type, exc, self._tb)
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/pkg_resources/_vendor/six.py", line 685, in reraise
        raise value.with_traceback(tb)
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/sandbox.py", line 154, in save_modules
        yield saved
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/sandbox.py", line 195, in setup_context
        yield
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/sandbox.py", line 250, in run_setup
        _execfile(setup_script, ns)
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/sandbox.py", line 45, in _execfile
        exec(code, globals, locals)
      File "/tmp/easy_install-8ftkx85p/pycparser-2.18/setup.py", line 54, in <module>
        'Topic :: Database :: Front-Ends',
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/__init__.py", line 129, in setup
        return distutils.core.setup(**attrs)
      File "/opt/python/3.7-dev/lib/python3.7/distutils/core.py", line 148, in setup
        dist.run_commands()
      File "/opt/python/3.7-dev/lib/python3.7/distutils/dist.py", line 966, in run_commands
        self.run_command(cmd)
      File "/opt/python/3.7-dev/lib/python3.7/distutils/dist.py", line 985, in run_command
        cmd_obj.run()
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/command/bdist_egg.py", line 218, in run
        os.path.join(archive_root, 'EGG-INFO'), self.zip_safe()
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/command/bdist_egg.py", line 269, in zip_safe
        return analyze_egg(self.bdist_dir, self.stubs)
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/command/bdist_egg.py", line 379, in analyze_egg
        safe = scan_module(egg_dir, base, name, stubs) and safe
      File "/home/travis/virtualenv/python3.7-dev/lib/python3.7/site-packages/setuptools/command/bdist_egg.py", line 416, in scan_module
        code = marshal.load(f)
    ValueError: bad marshal data (unknown type code)
    
    ----------------------------------------
Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-build-v2tv6uqy/psycopg2cffi/