[Cryptography-dev] Buildroot support

[Mauro Condarelli]

Hi,
I am trying to port cryptography to a Buildroot-based ARM system.

Unfortunately basic cross-compilation fails with the message below.
Since I am not a Python programmer and I just need Cryptography as a prerequisite for autobahn I am unable to understand what went wrong.

It seems to me compilation is trying to use on Host (x86_64) a shared lib (/home/mcon/emotiq/new/Buildroot/output/target/usr/lib/python2.7/site-packages/_cffi_backend.so) meant to run on Target (ARM).

Can someone help, please?

Thanks in Advance
Mauro

(cd /home/mcon/emotiq/new/Buildroot/output/build/python-cryptography-1.2.1//; PATH="/home/mcon/emotiq/new/Buildroot/output/host/bin:/home/mcon/emotiq/new/Buildroot/output/host/sbin:/home/mcon/emotiq/new/Buildroot/output/host/usr/bin:/home/mcon/emotiq/new/Buildroot/output/host/usr/sbin:/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games" CC="/home/mcon/emotiq/new/Buildroot/output/host/usr/bin/arm-buildroot-linux-gnueabi-gcc" CFLAGS="-D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64  -O3 " LDFLAGS="" LDSHARED="/home/mcon/emotiq/new/Buildroot/output/host/usr/bin/arm-buildroot-linux-gnueabi-gcc -shared" PYTHONPATH="/home/mcon/emotiq/new/Buildroot/output/target/usr/lib/python2.7/sysconfigdata/:/home/mcon/emotiq/new/Buildroot/output/target/usr/lib/python2.7/site-packages/" _python_sysroot=/home/mcon/emotiq/new/Buildroot/output/host/usr/arm-buildroot-linux-gnueabi/sysroot _python_prefix=/usr _python_exec_prefix=/usr 
/home/mcon/emotiq/new/Buildroot/output/host/usr/bin/python setup.py build --executable=/usr/bin/python )

Installed /home/mcon/emotiq/new/Buildroot/output/build/python-cryptography-1.2.1/.eggs/cffi-1.5.0-py2.7-linux-x86_64.egg
Searching for pycparser
Reading https://pypi.python.org/simple/pycparser/
Best match: pycparser 2.14
Downloading https://pypi.python.org/packages/source/p/pycparser/pycparser-2.14.tar.gz#md5=a2bc8d28c923b4fe2b2c3b4b51a4f935
Processing pycparser-2.14.tar.gz
Writing /tmp/easy_install-OMTOyu/pycparser-2.14/setup.cfg
Running pycparser-2.14/setup.py -q bdist_egg --dist-dir /tmp/easy_install-OMTOyu/pycparser-2.14/egg-dist-tmp-Oz3sRX
warning: no previously-included files matching 'yacctab.*' found under directory 'tests'
warning: no previously-included files matching 'lextab.*' found under directory 'tests'
warning: no previously-included files matching 'yacctab.*' found under directory 'examples'
warning: no previously-included files matching 'lextab.*' found under directory 'examples'
zip_safe flag not set; analyzing archive contents...
Moving pycparser-2.14-py2.7.egg to /home/mcon/emotiq/new/Buildroot/output/build/python-cryptography-1.2.1/.eggs

Installed /home/mcon/emotiq/new/Buildroot/output/build/python-cryptography-1.2.1/.eggs/pycparser-2.14-py2.7.egg
Traceback (most recent call last):
   File "setup.py", line 318, in <module>
     **keywords_with_side_effects(sys.argv)
   File "/home/mcon/emotiq/new/Buildroot/output/host/usr/lib/python2.7/distutils/core.py", line 111, in setup
     _setup_distribution = dist = klass(attrs)
   File "build/bdist.linux-x86_64/egg/setuptools/dist.py", line 272, in __init__
   File "/home/mcon/emotiq/new/Buildroot/output/host/usr/lib/python2.7/distutils/dist.py", line 287, in __init__
     self.finalize_options()
   File "build/bdist.linux-x86_64/egg/setuptools/dist.py", line 327, in finalize_options
   File "/home/mcon/emotiq/new/Buildroot/output/target/usr/lib/python2.7/site-packages/cffi/setuptools_ext.py", line 161, in cffi_modules
     add_cffi_module(dist, cffi_module)
   File "/home/mcon/emotiq/new/Buildroot/output/target/usr/lib/python2.7/site-packages/cffi/setuptools_ext.py", line 48, in add_cffi_module
     execfile(build_file_name, mod_vars)
   File "/home/mcon/emotiq/new/Buildroot/output/target/usr/lib/python2.7/site-packages/cffi/setuptools_ext.py", line 24, in execfile
     exec(code, glob, glob)
   File "src/_cffi_src/build_openssl.py", line 98, in <module>
     extra_link_args=extra_link_args(compiler_type()),
   File "src/_cffi_src/utils.py", line 64, in build_ffi_for_binding
     extra_link_args=extra_link_args,
   File "src/_cffi_src/utils.py", line 72, in build_ffi
     ffi = FFI()
   File "/home/mcon/emotiq/new/Buildroot/output/target/usr/lib/python2.7/site-packages/cffi/api.py", line 56, in __init__
     import _cffi_backend as backend
ImportError: /home/mcon/emotiq/new/Buildroot/output/target/usr/lib/python2.7/site-packages/_cffi_backend.so: wrong ELF class: ELFCLASS32
package/pkg-generic.mk:195: recipe for target '/home/mcon/emotiq/new/Buildroot/output/build/python-cryptography-1.2.1/.stamp_built' failed
make[1]: *** [/home/mcon/emotiq/new/Buildroot/output/build/python-cryptography-1.2.1/.stamp_built] Error 1