python - 无法加载基于 CI 构建的 Dylib

Question

我正在 Travis CI 上构建 Rust 二进制文件 (liblonlat_bng.dylib)，将其拉入 Cython 扩展(与 Cython 源 .c/.pyx 位于同一目录)，并进行测试它，也在 Travis CI 上(在不同的 repo 和构建中)。但是，Python 包的测试失败了，我不确定为什么:

----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/travis/build/urschrei/convertbng/venv/lib/python2.7/site-packages/nose/loader.py", line 418, in loadTestsFromName
    addr.filename, addr.module)
  File "/Users/travis/build/urschrei/convertbng/venv/lib/python2.7/site-packages/nose/importer.py", line 47, in importFromPath
    return self.importFromDir(dir_path, fqname)
  File "/Users/travis/build/urschrei/convertbng/venv/lib/python2.7/site-packages/nose/importer.py", line 94, in importFromDir
    mod = load_module(part_fqname, fh, filename, desc)
  File "/Users/travis/build/urschrei/convertbng/test/test_convertbng.py", line 15, in <module>
    from convertbng.cutil import convert_bng as cconvert_bng
ImportError: dlopen(/Users/travis/build/urschrei/convertbng/convertbng/cutil.so, 2): Library not loaded: /Users/travis/build/urschrei/lonlat_bng/target/x86_64-apple-darwin/release/liblonlat_bng.dylib
  Referenced from: /Users/travis/build/urschrei/convertbng/convertbng/cutil.so
  Reason: image not found

这是来自 Travis 的包的 OSX 构建输出:

Installing collected packages: convertbng
  Running setup.py develop for convertbng
    Running command /Users/travis/build/urschrei/convertbng/venv/bin/python2.7 -c "import setuptools, tokenize;__file__='/Users/travis/build/urschrei/convertbng/setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" develop --no-deps
    running develop
    running egg_info
    writing requirements to convertbng.egg-info/requires.txt
    writing convertbng.egg-info/PKG-INFO
    writing top-level names to convertbng.egg-info/top_level.txt
    writing dependency_links to convertbng.egg-info/dependency_links.txt
    warning: manifest_maker: standard file '-c' not found
    reading manifest file 'convertbng.egg-info/SOURCES.txt'
    reading manifest template 'MANIFEST.in'
    writing manifest file 'convertbng.egg-info/SOURCES.txt'
    running build_ext
    building 'convertbng.cutil' extension
    creating build
    creating build/temp.macosx-10.11-x86_64-2.7
    creating build/temp.macosx-10.11-x86_64-2.7/convertbng
    clang -fno-strict-aliasing -fno-common -dynamic -g -O2 -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -I. -Iconvertbng -I/usr/local/Cellar/python/2.7.11/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c convertbng/cutil.c -o build/temp.macosx-10.11-x86_64-2.7/convertbng/cutil.o -O3
    [unused function warnings]
    creating build/lib.macosx-10.11-x86_64-2.7
    creating build/lib.macosx-10.11-x86_64-2.7/convertbng
    clang -bundle -undefined dynamic_lookup build/temp.macosx-10.11-x86_64-2.7/convertbng/cutil.o -L. -Lconvertbng -llonlat_bng -o build/lib.macosx-10.11-x86_64-2.7/convertbng/cutil.so
    copying build/lib.macosx-10.11-x86_64-2.7/convertbng/cutil.so -> convertbng
    Creating /Users/travis/build/urschrei/convertbng/venv/lib/python2.7/site-packages/convertbng.egg-link (link to .)
    Adding convertbng 0.4.14 to easy-install.pth file
    Installed /Users/travis/build/urschrei/convertbng
Successfully installed convertbng

这是 Linux Travis 的输出，它成功地将 dylib 定位在相对路径上。请注意 -R 的 $ORIGIN 参数，它不能在 OSX 上使用:

Installing collected packages: convertbng
  Running setup.py develop for convertbng
    Running command /usr/bin/python -c "import setuptools, tokenize;__file__='/home/travis/build/urschrei/convertbng/setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" develop --no-deps
    running develop
    running egg_info
    writing requirements to convertbng.egg-info/requires.txt
    writing convertbng.egg-info/PKG-INFO
    writing top-level names to convertbng.egg-info/top_level.txt
    writing dependency_links to convertbng.egg-info/dependency_links.txt
    warning: manifest_maker: standard file '-c' not found
    reading manifest file 'convertbng.egg-info/SOURCES.txt'
    writing manifest file 'convertbng.egg-info/SOURCES.txt'
    running build_ext
    building 'convertbng.cutil' extension
    creating build
    creating build/temp.linux-x86_64-2.7
    creating build/temp.linux-x86_64-2.7/convertbng
    x86_64-linux-gnu-gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -fPIC -I. -Iconvertbng -I/usr/include/python2.7 -c convertbng/cutil.c -o build/temp.linux-x86_64-2.7/convertbng/cutil.o -O3
    creating build/lib.linux-x86_64-2.7
    creating build/lib.linux-x86_64-2.7/convertbng
    x86_64-linux-gnu-gcc -pthread -shared -Wl,-O1 -Wl,-Bsymbolic-functions -Wl,-Bsymbolic-functions -Wl,-z,relro -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -D_FORTIFY_SOURCE=2 -g -fstack-protector --param=ssp-buffer-size=4 -Wformat -Werror=format-security build/temp.linux-x86_64-2.7/convertbng/cutil.o -L. -Lconvertbng -Wl,-R$ORIGIN -llonlat_bng -o build/lib.linux-x86_64-2.7/convertbng/cutil.so
    copying build/lib.linux-x86_64-2.7/convertbng/cutil.so -> convertbng
    Creating /usr/local/lib/python2.7/dist-packages/convertbng.egg-link (link to .)
    Adding convertbng 0.4.14 to easy-install.pth file
    Installed /home/travis/build/urschrei/convertbng
Successfully installed convertbng

其他细节:

• 我的 OS X 和 Travis 都在使用 XCode 7.3
• 二进制文件是在本地和 Travis 上使用相同的提交构建的
• 如果我在本地构建二进制文件，然后在我的包上运行 setup.py build_ext --inplace，测试通过
• 我使用在 Travis 上使用相同提交构建的 .so 为 Linux 运行相同的安装，并且测试通过
• 如果我将 Travis 构建的 .dylib 复制到我的本地机器，然后运行 ​​setup.py build_ext --inplace，测试将失败并出现与 Travis 相同的错误。

我对发生的事情感到很困惑。二进制文件中有什么我应该看的吗？ otool -l 输出略有不同。例如:

本地:

cmd LC_LOAD_DYLIB
cmdsize 56
name /usr/lib/libSystem.B.dylib (offset 24)
time stamp 2 Thu Jan  1 01:00:02 1970
current version 1226.10.1

特拉维斯:

cmd LC_LOAD_DYLIB
cmdsize 56
name /usr/lib/libSystem.B.dylib (offset 24)
time stamp 2 Thu Jan  1 00:00:02 1970
current version 1225.1.1

通过 Linux 作业的链接:https://travis-ci.org/urschrei/convertbng/jobs/136730347
链接到失败的 OSX 作业:https://travis-ci.org/urschrei/convertbng/jobs/136730348

更新:这绝对是因为库名。如果我使用 install_name_tool 将 dylib 位置更改为 @loader_path/liblonlat_bng.dylib:

install_name_tool -change /Users/travis/build/urschrei/lonlat_bng/target/x86_64-apple-darwin/release/liblonlat_bng.dylib @loader_path/liblonlat_bng.dylib convertbng/cutil.so

Travis 构建的可执行文件将在我的本地机器上运行。但是，Travis 似乎有一个损坏的 install_name_tool 安装，我无法将正确的调用从 setup.py 传递给 cutil.so >。我已经尝试将 extra_link_args 设置为 ['-Wl,-rpath,'+'@loader_path/liblonlat_bng.dylib']，这会生成

/usr/bin/clang -bundle -undefined dynamic_lookup -arch i386 -arch x86_64 -g build/temp.macosx-10.6-intel-2.7/convertbng/cutil.o -L. -Lconvertbng -llonlat_bng -o build/lib.macosx-10.6-intel-2.7/convertbng/cutil.so -Wl,-rpath,@loader_path/liblonlat_bng.dylib

但如果我这样做，我的测试仍然会失败。

更新 2:当使用 cargo 构建时，我可以在链接阶段修复 dylib 的 install_name:

RUSTFLAGS="-C link-args=-Wl,-install_name,@rpath/liblonlat_bng.dylib" cargo build --release

这行得通。但我怀疑我的 setup.py Extension 设置有误:

# only append the runtime dir on Linux
rdirs = []
ldirs = []
if sys.platform != 'darwin':
    # from http://stackoverflow.com/a/10252190/416626
    # the $ORIGIN trick is not perfect, though
    rdirs = ['$ORIGIN']
if sys.platform == 'darwin':
    ldirs = ['-Wl,-rpath,'+'@loader_path/liblonlat_bng.dylib']

extensions = Extension("convertbng.cutil",
                    sources=["convertbng/cutil" + suffix],
                    libraries=["lonlat_bng"],
                    include_dirs=['.', 'convertbng'],
                    library_dirs=['.', 'convertbng'],
                    runtime_library_dirs=rdirs,
                    extra_compile_args=["-O3"],
                    extra_link_args=ldirs
) 

Answer 1

我遇到了同样的问题，我认为这是 Distutils 中的错误。我已经提出了解决此问题的拉取请求，并且还提出了一种解决方法。参见 https://github.com/python/cpython/pull/12418

你能在你的 setup.py 中尝试以下吗？

from Cython.Distutils.build_ext import new_build_ext as build_ext
# alternative:
# from distutils.command import build_ext

class my_build_ext(build_ext):
    """Workaround for rpath bug in distutils for OSX."""

    def finalize_options(self):
        super().finalize_options()
        # Special treatment of rpath in case of OSX, to work around python
        # distutils bug 36353. This constructs proper rpath arguments for clang.
        # See https://bugs.python.org/issue36353
        if sys.platform[:6] == "darwin":
            for path in self.rpath:
                for ext in self.extensions:
                    ext.extra_link_args.append("-Wl,-rpath," + path)
            self.rpath[:] = []

setup(
    cmdclass={'build_ext': my_build_ext}
    # ...
)