Python 3.1.1 with --enable-shared : will not build any extensions

Summary: Building Python 3.1 on RHEL 5.3 64 bit with --enable-shared fails to compile all extensions. Building "normal" works fine without any problems.

Please note that this question may seem to blur the line between programming and system administration. However, I believe that because it has to deal directly with getting language support in place, and it very much has to do with supporting the process of programming, that I would cross-post it here. Also at: https://serverfault.com/questions/73196/python-3-1-1-with-enable-shared-will-not-build-any-extensions. Thank you!

Problem:

Building Python 3.1 on RHEL 5.3 64 bit with --enable-shared fails to compile all extensions. Building "normal" works fine without any problems.

I can build python 3.1 just fine, but when built as a shared library, it emits many warnings (see below), and refuses to build any of the c based modules. Despite this failure, I can still build mod_wsgi 3.0c5 against it, and run it under apache. Needless to say, the functionality of Python is greatly reduced...

Interesting to note that Python 3.2a0 (from svn) compiles fine with --enable-shared, and mod_wsgi compiles fine against it. But when starting apache, I get:

Cannot load 开发者_Go百科/etc/httpd/modules/mod_wsgi.so into server: /etc/httpd/modules/mod_wsgi.so: undefined symbol: PyCObject_FromVoidPtr

The project that this is for is a long-term project, so I'm okay with alpha quality software if needed. Here are some more details on the problem.

Host:

• Dell PowerEdge
• Intel Xenon
• RHEL 5.3 64bit
• Nothing "special"

Build:

• Python 3.1.1 source distribution
• Works fine with ./configure
• Does not work fine with ./configure --enable-shared

(export CFLAGS="-fPIC" has been done)

make output

gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -I. -IInclude -I./Include -fPIC -DPy_BUILD_CORE -c ./Modules/_weakref.c -o Modules/_weakref.o

building 'bz2' extension gcc -pthread -fPIC -fno-strict-aliasing -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -I. -I./Include -I/usr/local/include -IInclude -I/home/build/RPMBUILD/BUILD/Python-3.1.1 -c /home/build/RPMBUILD/BUILD/Python-3.1.1/Modules/bz2module.c -o build/temp.linux-x86_64-3.1/home/build/RPMBUILD/BUILD/Python-3.1.1/Modules/bz2module.o gcc -pthread -shared -fno-strict-aliasing -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes build/temp.linux-x86_64-3.1/home/build/RPMBUILD/BUILD/Python-3.1.1/Modules/bz2module.o -L/usr/local/lib -L. -lbz2 -lpython3.1 -o build/lib.linux-x86_64-3.1/bz2.so /usr/bin/ld: /usr/local/lib/libpython3.1.a(abstract.o): relocation R_X86_64_32 against 'a local symbol' can not be used when making a shared object; recompile with -fPIC

Failed to build these modules:
_bisect            _codecs_cn         _codecs_hk
_codecs_iso2022    _codecs_jp         _codecs_kr
_codecs_tw         _collections       _csv
_ctypes            _ctypes_test       _curses
_curses_panel      _dbm               _elementtree
_gdbm              _hashlib           _heapq
_json              _lsprof            _multibytecodec
_multiprocessing   _pickle            _random
_socket            _sqlite3           _ssl
_struct            _testcapi          array
atexit             audioop            binascii
bz2                cmath              crypt
datetime           fcntl              grp
itertools          math               mmap
nis                operator           ossaudiodev
parser             pyexpat            readline
resource           select             spwd
syslog             termios            time
unicodedata        zlib

Something is wrong with your build environment. It is picking up a libpython3.1.a from /usr/local/lib; this confuses the error messages. It tries linking with that library, which fails - however, it shouldn't have tried that in the first place, since it should have used the libpython that it just built. I recommend taking the Python 3.1 installation in /usr/local out of the way.

You don't show in your output whether a libpython3.1.so.1.0 was created in the build tree; it would be important to find out whether it exists, how it was linked, and what symbols it has exported.

/usr/local/lib has been added to the library include path at compile time:

-L/usr/local/lib -L.

Its common for compile time to look in multiple 'common' paths for libraries (/usr/lib, /usr/local/lib, ./, etc) but also, it's possibly picking up /usr/local/lib from the environment variable LD_LIBRARY_PATH and tacking it on to the build command.