環境

主機： ubuntu14.04 64bit

開發板： qemu + vexpress-a9 （參考： http://www.cnblogs.com/pengdonglin137/p/6442583.html）

工具鏈： arm-none-linux-gnueabi-gcc  (gcc version 4.8.3 20140320)

Python版本： Python-2.7.13

前面一篇博文（交叉編譯Python-2.7.13到ARM（aarch32）平臺）介紹了移植python到aarch32上面，但是發現有很多模塊都不能用，可以在板子上面執行下面的命令測試一下：

 1 [root@vexpress ]# python /usr/lib/python2.7/test/test___all__.py

 2 Traceback (most recent call last):

 3   File "/usr/lib/python2.7/test/test___all__.py", line 3, in

 4     import unittest

 5   File "/usr/lib/python2.7/unittest/__init__.py", line 58, in

 6     from .result import TestResult

 7   File "/usr/lib/python2.7/unittest/result.py", line 9, in

 8     from . import util

 9   File "/usr/lib/python2.7/unittest/util.py", line 2, in

10     from collections import namedtuple, OrderedDict

11   File "/usr/lib/python2.7/collections.py", line 20, in

12     from _collections import deque, defaultdict

13 ImportError: No module named _collections

可以看到這里找不到_collections模塊。

對比x86_64的編譯結果：

1 ls x86_64/build/lib.linux-x86_64-2.7/

2 array.so*       _codecs_hk.so*       cPickle.so*       _curses_panel.so*  future_builtins.so*  itertools.so*      mmap.so*              parser.so*    _socket.so*   _sysconfigdata.py   time.so*

3 audioop.so*     _codecs_iso2022.so*  crypt.so*         _curses.so*        grp.so*              _json.so*          _multibytecodec.so*   pyexpat.so*   spwd.so*      _sysconfigdata.pyc  unicodedata.so*

4 binascii.so*    _codecs_jp.so*       cStringIO.so*     datetime.so*       _hashlib.so*         linuxaudiodev.so*  _multiprocessing.so*  _random.so*   _sqlite3.so*  _sysconfigdata.pyo  zlib.so*

5 _bisect.so*     _codecs_kr.so*       _csv.so*          _elementtree.so*   _heapq.so*           _locale.so*        nis.so*               readline.so*  _ssl.so*      syslog.so*

6 cmath.so*       _codecs_tw.so*       _ctypes.so*       fcntl.so*          _hotshot.so*         _lsprof.so*        operator.so*          resource.so*  strop.so*     termios.so*

7 _codecs_cn.so*  _collections.so*     _ctypes_test.so*  _functools.so*     _io.so*              math.so*           ossaudiodev.so*       select.so*    _struct.so*   _testcapi.so*

而aarch32的編譯結果：

1 $ls aarch32/build/lib.linux2-arm-2.7/

2 audioop.so*     _codecs_iso2022.so*  _codecs_tw.so*  _ctypes.so*       _elementtree.so*     _json.so*          mmap.so*              nis.so*      resource.so*        termios.so*

3 _codecs_cn.so*  _codecs_jp.so*       crypt.so*       _ctypes_test.so*  future_builtins.so*  linuxaudiodev.so*  _multibytecodec.so*   parser.so*   _sysconfigdata.py   _testcapi.so*

4 _codecs_hk.so*  _codecs_kr.so*       _csv.so*        datetime.so*      _hotshot.so*         _lsprof.so*        _multiprocessing.so*  pyexpat.so*  _sysconfigdata.pyc

可以看到，aarch32上面缺少了很多庫， 比如_collections.so，將來這些庫會被安裝到/usr/lib/python2.7/lib-dynload下面， 所以下面要說的就是將缺少的這些庫弄回來！

正文

1、通過分析setup.py發現問題

在函數build_extensions中剛開始self.extensions中存放的是需要編譯庫， 通過在加打印：

 1 diff --git a/setup.py b/setup.py

 2 index 54054c2..bc16bb1 100644

 3 --- a/setup.py

 4 +++ b/setup.py

 5 @@ -178,6 +178,7 @@ class PyBuildExt(build_ext):

 6  

 7      def build_extensions(self):

 8  

 9 +        print "build_extensions enter."

10          # Detect which modules should be compiled

11          missing = self.detect_modules()

12  

13 @@ -191,6 +192,9 @@ class PyBuildExt(build_ext):

14              extensions.append(ctypes)

15          self.extensions = extensions

16  

17 +        for ext in self.extensions:

18 +            print "extensions: ", ext.name

19 +

20          # Fix up the autodetected modules, prefixing all the source files

21          # with Modules/ and adding Python's include directory to the path.

22          (srcdir,) = sysconfig.get_config_vars('srcdir')

23 @@ -217,6 +221,8 @@ class PyBuildExt(build_ext):

24          # Python header files

25          headers = [sysconfig.get_config_h_filename()]

26          headers += glob(os.path.join(sysconfig.get_path('include'), "*.h"))

27 +

28 +        print "builtin_module_names: ", sys.builtin_module_names

29          for ext in self.extensions[:]:

30              ext.sources = [ find_module_file(filename, moddirlist)

31                              for filename in ext.sources ]

32 @@ -248,10 +254,15 @@ class PyBuildExt(build_ext):

33                  remove_modules.append(line[0])

34              input.close()

35  

36 +        print "remove_modules: ", remove_modules

37 +

38          for ext in self.extensions[:]:

39              if ext.name in remove_modules:

40                  self.extensions.remove(ext)

41  

42 +        for ext in self.extensions[:]:

43 +            print "extensions: ", ext.name

44 +

45          # When you run "make CC=altcc" or something similar, you really want

46          # those environment variables passed into the setup.py phase.  Here's

47          # a small set of useful ones.

48 @@ -1618,13 +1629,13 @@ class PyBuildExt(build_ext):

49  

50  

51          # Platform-specific libraries

52 -        if host_platform == 'linux2':

53 +        if host_platform == 'linux2' or host_platform == 'linux2-arm':

54              # Linux-specific modules

55              exts.append( Extension('linuxaudiodev', ['linuxaudiodev.c']) )

56          else:

57              missing.append('linuxaudiodev')

58  

59 -        if (host_platform in ('linux2', 'freebsd4', 'freebsd5', 'freebsd6',

60 +        if (host_platform in ('linux2','linux2-arm' 'freebsd4', 'freebsd5', 'freebsd6',

61                          'freebsd7', 'freebsd8')

62              or host_platform.startswith("gnukfreebsd")):

63              exts.append( Extension('ossaudiodev', ['ossaudiodev.c']) )

64 @@ -1755,6 +1766,10 @@ class PyBuildExt(build_ext):

65  ##         ext = Extension('xx', ['xxmodule.c'])

66  ##         self.extensions.append(ext)

67  

68 +#        print "missing: ", missing

69 +#        for ext in self.extensions:

70 +#            print "extensions: ", ext.name

71 +

72          return missing

73  

74      def detect_tkinter_explicitly(self):

75 @@ -2229,6 +2244,8 @@ Topic :: Software Development

76  """

77  

78  def main():

79 +    print "sys.path: ", sys.path

80 +    print "cross_compiling: ", cross_compiling

81      # turn off warnings when deprecated modules are imported

82      import warnings

83      warnings.filterwarnings("ignore",category=DeprecationWarning)

然后執行./mk2_make.sh可以看到：

 1 sys.path:  ['/home/pengdonglin/src/qemu/python_cross_compile/Python-2.7.13', '/home/pengdonglin/src/qemu/python_cross_compile/aarch32/build/lib.linux2-arm-2.7', '/home/pengdonglin/src/qemu/python_cross_compile/Python-2.7.13/Lib', '/home/pengdonglin/src/qemu/python_cross_compile/Python-2.7.13/Lib/plat-linux2', '/usr/lib/python2.7', '/usr/lib/python2.7/plat-x86_64-linux-gnu', '/usr/lib/python2.7/lib-tk', '/usr/lib/python2.7/lib-old', '/usr/lib/python2.7/lib-dynload']