Error installing bcrypt with pip on OS X: can'

问题:

I'm getting this error when trying to install bcrypt with pip. I have libffi installed in a couple places (the Xcode OS X SDK, and from homebrew), but I don't know how to tell pip to look for it. Any suggestions?

Downloading/unpacking bcrypt==1.0.2 (from -r requirements.txt (line 41))
  Running setup.py egg_info for package bcrypt
    OS/X: confusion between 'cc' versus 'gcc' (see issue 123)
    will not use '__thread' in the C code
    c/_cffi_backend.c:14:10: fatal error: 'ffi.h' file not found
    #include <ffi.h>
             ^
    1 error generated.
    Traceback (most recent call last):
      File "<string>", line 16, in <module>
      File "/Users/cody/virtualenvs/analytics/build/bcrypt/setup.py", line 104, in <module>
        "Programming Language :: Python :: 3.3",
      File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/distutils/core.py", line 112, in setup
        _setup_distribution = dist = klass(attrs)
      File "build/bdist.macosx-10.9-intel/egg/setuptools/dist.py", line 239, in __init__
      File "build/bdist.macosx-10.9-intel/egg/setuptools/dist.py", line 264, in fetch_build_eggs
      File "build/bdist.macosx-10.9-intel/egg/pkg_resources.py", line 620, in resolve
        dist = best[req.key] = env.best_match(req, ws, installer)
      File "build/bdist.macosx-10.9-intel/egg/pkg_resources.py", line 858, in best_match
        return self.obtain(req, installer) # try and download/install
      File "build/bdist.macosx-10.9-intel/egg/pkg_resources.py", line 870, in obtain
        return installer(requirement)
      File "build/bdist.macosx-10.9-intel/egg/setuptools/dist.py", line 314, in fetch_build_egg
      File "build/bdist.macosx-10.9-intel/egg/setuptools/command/easy_install.py", line 593, in easy_install

      File "build/bdist.macosx-10.9-intel/egg/setuptools/command/easy_install.py", line 623, in install_item

      File "build/bdist.macosx-10.9-intel/egg/setuptools/command/easy_install.py", line 811, in install_eggs

      File "build/bdist.macosx-10.9-intel/egg/setuptools/command/easy_install.py", line 1017, in build_and_install

      File "build/bdist.macosx-10.9-intel/egg/setuptools/command/easy_install.py", line 1005, in run_setup

    distutils.errors.DistutilsError: Setup script exited with error: command 'cc' failed with exit status 1
    Complete output from command python setup.py egg_info:
    OS/X: confusion between 'cc' versus 'gcc' (see issue 123)

will not use '__thread' in the C code

c/_cffi_backend.c:14:10: fatal error: 'ffi.h' file not found

#include <ffi.h>

         ^

1 error generated.

Traceback (most recent call last):

  File "<string>", line 16, in <module>

  File "/Users/cody/virtualenvs/analytics/build/bcrypt/setup.py", line 104, in <module>

    "Programming Language :: Python :: 3.3",

  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/distutils/core.py", line 112, in setup

    _setup_distribution = dist = klass(attrs)

  File "build/bdist.macosx-10.9-intel/egg/setuptools/dist.py", line 239, in __init__

  File "build/bdist.macosx-10.9-intel/egg/setuptools/dist.py", line 264, in fetch_build_eggs

  File "build/bdist.macosx-10.9-intel/egg/pkg_resources.py", line 620, in resolve

    dist = best[req.key] = env.best_match(req, ws, installer)

  File "build/bdist.macosx-10.9-intel/egg/pkg_resources.py", line 858, in best_match

    return self.obtain(req, installer) # try and download/install

  File "build/bdist.macosx-10.9-intel/egg/pkg_resources.py", line 870, in obtain

    return installer(requirement)

  File "build/bdist.macosx-10.9-intel/egg/setuptools/dist.py", line 314, in fetch_build_egg

  File "build/bdist.macosx-10.9-intel/egg/setuptools/command/easy_install.py", line 593, in easy_install



  File "build/bdist.macosx-10.9-intel/egg/setuptools/command/easy_install.py", line 623, in install_item



  File "build/bdist.macosx-10.9-intel/egg/setuptools/command/easy_install.py", line 811, in install_eggs



  File "build/bdist.macosx-10.9-intel/egg/setuptools/command/easy_install.py", line 1017, in build_and_install



  File "build/bdist.macosx-10.9-intel/egg/setuptools/command/easy_install.py", line 1005, in run_setup



distutils.errors.DistutilsError: Setup script exited with error: command 'cc' failed with exit status 1

----------------------------------------
Command python setup.py egg_info failed with error code 1 in /Users/cody/virtualenvs/analytics/build/bcrypt

回答1:

Without using sudo and CFLAGS and CPPFLAGS (unnecessary for pip):

$ brew install pkg-config libffi
$ export PKG_CONFIG_PATH=/usr/local/Cellar/libffi/3.0.13/lib/pkgconfig/
$ pip install bcrypt

回答2:

I finally got it working with the following with a little help from these posts:

brew install pkg-config libffi
sudo bash
export CFLAGS=-Qunused-arguments
export CPPFLAGS=-Qunused-arguments
export PKG_CONFIG_PATH=/usr/local/Cellar/libffi/3.0.13/lib/pkgconfig/
pip install bcrypt

回答3:

Xcode was already installed for me (as mentioned in the question itself that it does provide the ffi.h header), but for some reason that didn't populate /usr/include (as Zachary Young mentioned). I dug around to see why the /usr/include wasn't populated and found that the following command fixed it:

$ xcode-select --install

Missing /usr/include after Yosemite and Xcode install?

回答4:

Update 26/Aug/15

I think TA's answer is better in that it's handled by the system.

---

First off, I'm loathe to install Brew or Ports, but that's another issue.

I've been trying to pip install cryptography, which depends on cffi, which imports ffi.h.

I am curious why no one addressed that he (and me, and I believe others) have ffi installed with Xcode:

locate ffi.h
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.10.sdk/usr/include/ffi/ffi.h

since the error is specifically about "not finding" ffi.h with the following build command:

c/_cffi_backend.c:14:10: fatal error: 'ffi.h' file not found
#include <ffi.h>
...
...
/usr/bin/clang ...{omitted}... I/usr/include/ffi -I/usr/include/libffi

I have ffi.h, it's just that the system thinks it should be in /usr/include/....

My /usr/include directory happens to be empty, and not linked to anything, so I just linked the directory/file in question, to the place where it's not being found:

ln -fs {THAT_XCODE_SDK_FFI_PATH_FROM_ABOVE} /usr/include/ffi

I can now install and build cffi and cryptography.

I'm very novice when it comes to understanding build-chain/linking dynamics, and if this is bad, I don't get it... so, please let me know.