[Python-bugs-list] [ python-Bugs-413582 ] g++ must be called for c++ extensions

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Bugs item #413582, was opened at 2001-04-03 20:42
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Category: Distutils
Group: None
Status: Open
Resolution: None
Priority: 5
Submitted By: Nobody/Anonymous (nobody)
>Assigned to: Nobody/Anonymous (nobody)
Summary: g++ must be called for c++ extensions

Initial Comment:
When building c++ extension using distutils setup,
the compiler that was used to build python distribution
is always called. On Linux, it is normally gcc.
When gcc is called to link shared library, it does not
link certain c++ runtime stuff. As a result, when
extension is imported, missing symbols are reported,
e.g.:
>>> import ex_ext1
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
ImportError: ./ex_ext1.so: undefined symbol:
__vt_13runtime_error
>>>
I tried to use "extra_link_args = ['-x c++']" in
setup.py (it tells gcc to link as c++), but that gets
added to the end of compiler's command line, which
results in:
gcc -shared build/temp.linux-i686-2.1/ex_ext1.o
-L../boost/libs/python -lboost_python -o
build/lib.linux-i686-2.1/ex_ext1.so -x c++
gcc: Warning: `-x  c++' after last input file has no
effect

Proposed solution: either use CXX= variable from Python
Makefile when c++ files are involved, or prepend
extra_link_args to compiler's arguments instead of
appending them.


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Comment By: Guido van Rossum (gvanrossum)
Date: 2002-04-18 08:55

Message:
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reassigned to amk who should know

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Comment By: Anthony Baxter (anthonybaxter)
Date: 2002-04-18 02:47

Message:
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can this be closed as a duplicate of 454030? That one
has a real submitter, and some more info...


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Comment By: Guido van Rossum (gvanrossum)
Date: 2001-04-10 11:51

Message:
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Assigning this to Andrew, who is the current distutils
maintainer.


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Comment By: Andrei Tovtchigretchko (andreitd)
Date: 2001-04-04 20:23

Message:
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user_id=189208

Follow-up:
If I link with a static library (-lboost_python is
libboost_python.a in bug post example), the problem shows.
If I link with shared c++ library (libboost_python.so),
everything is ok.

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