segfault 使用 numpy 的 lapack_lite 在 osx 上进行多处理，而不是 linux

The following test code segfaults for me on OSX 10.7.3, but not other machines:

from __future__ import print_function

import numpy as np
import multiprocessing as mp
import scipy.linalg

def f(a):
    print("about to call")

    ### these all cause crashes
    sign, x = np.linalg.slogdet(a)
    #x = np.linalg.det(a)
    #x = np.linalg.inv(a).sum()

    ### these are all fine
    #x = scipy.linalg.expm3(a).sum()
    #x = np.dot(a, a.T).sum()

    print("result:", x)
    return x

def call_proc(a):
    print("
calling with multiprocessing")
    p = mp.Process(target=f, args=(a,))
    p.start()
    p.join()


if __name__ == '__main__':
    import sys
    n = int(sys.argv[1]) if len(sys.argv) > 1 else 50

    a = np.random.normal(0, 2, (n, n))
    f(a)

    call_proc(a)
    call_proc(a)

其中一个段错误的示例输出:

$ python2.7 test.py
about to call
result: -4.96797718087

calling with multiprocessing
about to call

calling with multiprocessing
about to call

$ otool -L `python3.2 -c 'from numpy.core import _dotblas; print(_dotblas.__file__)'`
/Library/Frameworks/Python.framework/Versions/3.2/lib/python3.2/site-packages/numpy/core/_dotblas.so:
    /System/Library/Frameworks/Accelerate.framework/Versions/A/Accelerate (compatibility version 1.0.0, current version 4.0.0)
    /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 125.2.1)