Ufdjrw

Python library gevent, version 0.13.6 (the current version on PyPI) will not pip install on OS X Lion, Python 2.7 (and probably others.) It works fine on Snow Leopard.

How can I get this library installed?

Bonus points if it can be done using pip install, rather than a manual or custom process, because then it will play nicely with automated builds.

Here is my pip install output:

pip install gevent
Downloading/unpacking gevent
 Running setup.py egg_info for package gevent

Requirement already satisfied (use --upgrade to upgrade): greenlet in ./tl_env/lib/python2.7/site-packages (from gevent)
Installing collected packages: gevent
 Running setup.py install for gevent
 building 'gevent.core' extension
 gcc-4.2 -fno-strict-aliasing -fno-common -dynamic -isysroot /Developer/SDKs/MacOSX10.6.sdk -arch i386 -arch x86_64 -g -O2 -DNDEBUG -g -O3 -I/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c gevent/core.c -o build/temp.macosx-10.6-intel-2.7/gevent/core.o
 In file included from gevent/core.c:225:
 gevent/libevent.h:9:19: error: event.h: No such file or directory
 gevent/libevent.h:38:20: error: evhttp.h: No such file or directory
 gevent/libevent.h:39:19: error: evdns.h: No such file or directory
 gevent/core.c:361: error: field ‘ev’ has incomplete type
 gevent/core.c:741: warning: parameter names (without types) in function declaration
 gevent/core.c: In function ‘__pyx_f_6gevent_4core___event_handler’:
 gevent/core.c:1619: error: ‘EV_READ’ undeclared (first use in this function)
 gevent/core.c:1619: error: (Each undeclared identifier is reported only once
 gevent/core.c:15376: warning: assignment makes pointer from integer without a cast
 [... about 1000 more lines of compiler errors...]
 gevent/core.c:15385: error: dereferencing pointer to incomplete type
 gevent/core.c: In function ‘__pyx_pf_6gevent_4core_4http___init__’:
 gevent/core.c:15559: warning: assignment makes pointer from integer without a cast
 gevent/core.c: At top level:
 gevent/core.c:21272: error: expected ‘)’ before ‘val’
 lipo: can't figure out the architecture type of: /var/folders/s5/t94kn0p10hdgxzx9_9sprpg40000gq/T//cczk54q7.out
 error: command 'gcc-4.2' failed with exit status 1
 Complete output from command /Users/jacob/code/toplevel/tl_env/bin/python -c "import setuptools;__file__='/Users/jacob/code/toplevel/tl_env/build/gevent/setup.py';exec(compile(open(__file__).read().replace('rn', 'n'), __file__, 'exec'))" install --single-version-externally-managed --record /var/folders/s5/t94kn0p10hdgxzx9_9sprpg40000gq/T/pip-s2hPd3-record/install-record.txt --install-headers /Users/jacob/code/toplevel/tl_env/bin/../include/site/python2.7:
 running install

running build

running build_py

running build_ext

building 'gevent.core' extension

gcc-4.2 -fno-strict-aliasing -fno-common -dynamic -isysroot /Developer/SDKs/MacOSX10.6.sdk -arch i386 -arch x86_64 -g -O2 -DNDEBUG -g -O3 -I/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c gevent/core.c -o build/temp.macosx-10.6-intel-2.7/gevent/core.o

Don't post the entire thing! That's too much! 90% of the time, the first error is enough...

gevent/libevent.h:9:19: error: event.h: No such file or directory

This means that the library which provides the event.h header is not installed. The library is called libevent (website).

In general, compilation errors like these are a flaw in the build scripts. The build script should give an error message that libevent is not installed, and it is a bug that it did not do so.

To get libevent from MacPorts and then manually tell compiler with CFLAGS environment variable where to find event.h and libevent while running pip.

sudo port install libevent
CFLAGS="-I /opt/local/include -L /opt/local/lib" pip install gevent

You can also use homebrew for installing libevent : brew install libevent

(from David Wolever's comment)

CFLAGS='-std=c99' pip install gevent

See in: Can't install gevent OSX 10.11

on OS X 10.11, clang uses c11 as the default, so just turn it back to c99.

After a while, I realized that the paths for the CFLAGS variable mentioned above works when installing libevent from port, but not from brew. The following worked for me (on OSX Mavericks):

$ brew install libevent
$ export CFLAGS="-I /usr/local/Cellar/libevent/2.0.21/include -L /usr/local/Cellar/libevent/2.0.21/lib"
$ pip install gevent

This is the way I found the easiest:

install libevent using homebrew

$ brew install libevent

install gevent

$ pip install gevent

This was the only way I could get it to work.