我正在浏览Cython文档并构建每个示例应用程序。我有点困在使用C库。成功构建.so文件并尝试将其导入名为test.py的python文件后，将引发以下错误。
$ python3.2 test.py
Traceback (most recent call last):
File "test.py", line 12, in <module>
from queue import Queue
ImportError: dlopen(/Users/jeremy/Development/labs/python/cython_lib_wrapper/queue.so, 2): Symbol not found: _queue_free
Referenced from: /Users/jeremy/Development/labs/python/cython_lib_wrapper/queue.so
Expected in: flat namespace
in /Users/jeremy/Development/labs/python/cython_lib_wrapper/queue.so
.so文件位于test.py文件旁边。所以，似乎应该找到它。 这是在OSX 10.6上使用Python 3.2运行最新版本的Cython。
任何见解？
编辑 - 添加构建命令和输出
$ python3.2 setup.py build_ext --inplace
running build_ext
cythoning queue.pyx to queue.c
building 'queue' extension
gcc-4.2 -fno-strict-aliasing -fno-common -dynamic -DNDEBUG -g -O3 -isysroot /Developer/SDKs/MacOSX10.6.sdk -arch i386 -arch x86_64 -isysroot /Developer/SDKs/MacOSX10.6.sdk -I/Library/Frameworks/Python.framework/Versions/3.2/include/python3.2m -c queue.c -o build/temp.macosx-10.6-intel-3.2/queue.o
queue.c: In function ‘__pyx_f_5queue_5Queue_append’:
queue.c:627: warning: cast to pointer from integer of different size
queue.c: In function ‘__pyx_f_5queue_5Queue_extend’:
queue.c:740: warning: cast to pointer from integer of different size
queue.c: In function ‘__pyx_f_5queue_5Queue_peek’:
queue.c:813: warning: cast from pointer to integer of different size
queue.c: In function ‘__pyx_f_5queue_5Queue_pop’:
queue.c:965: warning: cast from pointer to integer of different size
gcc-4.2 -bundle -undefined dynamic_lookup -arch i386 -arch x86_64 -isysroot /Developer/SDKs/MacOSX10.6.sdk -isysroot /Developer/SDKs/MacOSX10.6.sdk -g build/temp.macosx-10.6-intel-3.2/queue.o -o
编辑2 - 添加评论中要求的“otool”cmd
queue.so:
/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 125.2.0)
编辑3 - 添加“nm”输出
U ___stack_chk_fail
U ___stack_chk_guard
U _queue_free
U _queue_is_empty
U _queue_new
U _queue_peek_head
U _queue_pop_head
U _queue_push_tail
U dyld_stub_binder
grep cmd输出：
(undefined) external _queue_free (dynamically looked up)
答案 0 :(得分：6)
编辑：
啊，你没有提到你对libcalg中的代码有依赖性。在构建cextension时，需要编译和包含这些内容。
只需修改setup.py：
即可# setup.py
# ...
ext_modules = [Extension("queue", ["queue.pyx", "libcalg/queue.c"])]
# ...
我们可以退一步看看你是否可以建立一个非常简单的例子：
我已经尝试了以下（3个文件，myext.pyx，test.py，setup.py），它似乎工作正常。当然我在OS X 10.7上，所以它与你的环境不完全相同。为了排除差异，您可以复制这些差异并将其构建为完整性检查。
myext.pyx的内容：
# myext.pyx
def square(x):
return x * x
test.py的内容
# test.py
from myext import square
print "%d squared is %d"%(4, square(4))
setup.py的内容：
# setup.py
from distutils.core import setup
from distutils.extension import Extension
from Cython.Distutils import build_ext
ext_modules = [Extension("myext", ["myext.pyx"])]
setup(
name = 'Hello world app',
cmdclass = {'build_ext': build_ext},
ext_modules = ext_modules
)
我构建了包含这3个文件的目录：
cython_test$ /usr/bin/python setup.py build_ext --inplace
running build_ext
cythoning myext.pyx to myext.c
building 'myext' extension
creating build
creating build/temp.macosx-10.7-intel-2.7
llvm-gcc-4.2 -fno-strict-aliasing -fno-common -dynamic -g -Os -pipe -fno-common -fno-strict-aliasing -fwrapv -mno-fused-madd -DENABLE_DTRACE -DMACOSX -DNDEBUG -Wall -Wstrict-prototypes -Wshorten-64-to-32 -DNDEBUG -g -fwrapv -Os -Wall -Wstrict-prototypes -DENABLE_DTRACE -arch i386 -arch x86_64 -pipe -I/System/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c myext.c -o build/temp.macosx-10.7-intel-2.7/myext.o
llvm-gcc-4.2 -Wl,-F. -bundle -undefined dynamic_lookup -Wl,-F. -arch i386 -arch x86_64 build/temp.macosx-10.7-intel-2.7/myext.o -o /Users/steder/SO/cython_test/myext.so
cython_test$ python test.py
4 squared is 16:
我的环境有类似的otool输出，DYLD_LIBRARY_PATH也未设置，但nm -m显示为已定义的平方。
具体做法是：
00000000000011d0 (__DATA,__data) non-external ___pyx_k__square
00000000000011e0 (__DATA,__data) non-external ___pyx_mdef_5myext_square
0000000000001218 (__DATA,__bss) non-external ___pyx_n_s__square
0000000000000c80 (__TEXT,__text) non-external ___pyx_pf_5myext_square
请试一试，看看它在您的环境中显示的是什么。