"Illegal instruction: 4" on OS X 10.10.5

Hi,

I'm using Python 2.7.11 on OS X 10.10.5 and I get an illegal instruction error using Paramiko:

$ python
Python 2.7.11 (default, Jan 26 2016, 14:52:31) 
[GCC 4.2.1 Compatible Apple LLVM 7.0.2 (clang-700.1.81)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import paramiko
>>> paramiko.__version_info__
(1, 16, 0)
>>> paramiko.common.logging.basicConfig(level=paramiko.common.DEBUG)
>>> h = paramiko.SSHClient()
>>> h.connect('jumpbox.integration.publishing.service.gov.uk', username='alexmuller', key_filename='~/.ssh/id_rsa.pub')
DEBUG:paramiko.transport:starting thread (client mode): 0x3726950L
DEBUG:paramiko.transport:Local version/idstring: SSH-2.0-paramiko_1.16.0
DEBUG:paramiko.transport:Remote version/idstring: SSH-2.0-OpenSSH_6.6.1p1 Ubuntu-2ubuntu2.4
INFO:paramiko.transport:Connected (version 2.0, client OpenSSH_6.6.1p1)
DEBUG:paramiko.transport:kex algos:[u'curve25519-sha256@libssh.org', u'ecdh-sha2-nistp256', u'ecdh-sha2-nistp384', u'ecdh-sha2-nistp521', u'diffie-hellman-group-exchange-sha256', u'diffie-hellman-group-exchange-sha1', u'diffie-hellman-group14-sha1', u'diffie-hellman-group1-sha1'] server key:[u'ssh-rsa', u'ssh-dss'] client encrypt:[u'aes128-ctr', u'aes192-ctr', u'aes256-ctr', u'arcfour256', u'arcfour128', u'aes128-gcm@openssh.com', u'aes256-gcm@openssh.com', u'chacha20-poly1305@openssh.com', u'aes128-cbc', u'3des-cbc', u'blowfish-cbc', u'cast128-cbc', u'aes192-cbc', u'aes256-cbc', u'arcfour', u'rijndael-cbc@lysator.liu.se'] server encrypt:[u'aes128-ctr', u'aes192-ctr', u'aes256-ctr', u'arcfour256', u'arcfour128', u'aes128-gcm@openssh.com', u'aes256-gcm@openssh.com', u'chacha20-poly1305@openssh.com', u'aes128-cbc', u'3des-cbc', u'blowfish-cbc', u'cast128-cbc', u'aes192-cbc', u'aes256-cbc', u'arcfour', u'rijndael-cbc@lysator.liu.se'] client mac:[u'hmac-md5-etm@openssh.com', u'hmac-sha1-etm@openssh.com', u'umac-64-etm@openssh.com', u'umac-128-etm@openssh.com', u'hmac-sha2-256-etm@openssh.com', u'hmac-sha2-512-etm@openssh.com', u'hmac-ripemd160-etm@openssh.com', u'hmac-sha1-96-etm@openssh.com', u'hmac-md5-96-etm@openssh.com', u'hmac-md5', u'hmac-sha1', u'umac-64@openssh.com', u'umac-128@openssh.com', u'hmac-sha2-256', u'hmac-sha2-512', u'hmac-ripemd160', u'hmac-ripemd160@openssh.com', u'hmac-sha1-96', u'hmac-md5-96'] server mac:[u'hmac-md5-etm@openssh.com', u'hmac-sha1-etm@openssh.com', u'umac-64-etm@openssh.com', u'umac-128-etm@openssh.com', u'hmac-sha2-256-etm@openssh.com', u'hmac-sha2-512-etm@openssh.com', u'hmac-ripemd160-etm@openssh.com', u'hmac-sha1-96-etm@openssh.com', u'hmac-md5-96-etm@openssh.com', u'hmac-md5', u'hmac-sha1', u'umac-64@openssh.com', u'umac-128@openssh.com', u'hmac-sha2-256', u'hmac-sha2-512', u'hmac-ripemd160', u'hmac-ripemd160@openssh.com', u'hmac-sha1-96', u'hmac-md5-96'] client compress:[u'none', u'zlib@openssh.com'] server compress:[u'none', u'zlib@openssh.com'] client lang:[u''] server lang:[u''] kex follows?False
DEBUG:paramiko.transport:Kex agreed: diffie-hellman-group1-sha1
DEBUG:paramiko.transport:Cipher agreed: aes128-ctr
DEBUG:paramiko.transport:MAC agreed: hmac-sha2-256
DEBUG:paramiko.transport:Compression agreed: none
Illegal instruction: 4

Do you have any idea what could be going on here?

Reproduce the failure with Python 2.7.11, Paramiko 1.16.0, and OS X 10.10.5 using the SSHClient connection shown in the report. Start at the negotiation output, especially the agreed key exchange and cipher, and compare behavior across the reported environment. Done means the cause of the illegal instruction is identified and the issue has a confirmed fix or documented workaround.