Hi.
Thanks for the quick response.
The -defaultlib was left around from trying all kinds of
combinations of dmd and gcc. I am not used to gcc, and it will
take me some time to become properly acquainted with all the
options.
I simply could not get it to recognize libphobos no matter what
path settings I tried passing.
http://forum.dlang.org/thread/k3vfm9$1tq$1...@digitalmars.com?page=4
I don't know whether this was necessary, but I did manage to get
it to work after looking at a thread from a couple of years back.
I recompiled the D runtime and Phobos with position independent
code (PIC) and pointed everything to that version instead, and it
worked fine. (Just export PIC=True, rename the posix.mak to
Makefile, change the DMD path to /usr/sbin/dmd - in my case, and
it all worked).
Next step is to try calling D interface from Cython.
Laeeth
In case anyone else should struggle with this in future.
Makefile here:
PHOBOS_PATH=/opt/dmd2/src/phobos/generated/linux/release/64
pytestpy.so: pytest.d pytestpy.o
dmd -fPIC -c pytest.d #-shared -defaultlib=libphobos2.so
-L-rpath=.:${PHOBOS_PATH}
gcc -shared pytest.o pytestpy.o -o pytest.so -lphobos2 -lpthread
-lrt -L. -L${PHOBOS_PATH} -Wl,-rpath=.:${PHOBOS_PATH} -o
pytestpy.so -defaultlib=libphobos2.so -L-rpath=.:${PHOBOS_PATH}
pytest.o: %.d
dmd -c $<
pytestpy.o: pytestpy.pyx
cython pytestpy.pyx
gcc -fPIC -c pytestpy.c -o pytestpy.o -I/usr/include/python2.7
clean:
rm -f pytestpy.c pytest.o pytestpy.o pytest.so
pytest.d
extern (C) long pytest(long a)
{
return a*2;
}
pytestpy.pyx
cdef extern long pytest(long a)
cpdef pytestpy():
return pytest(109)
print pytest(102)
setup.py
from distutils.core import setup
from distutils.extension import Extension
from Cython.Build import cythonize
setup(
ext_modules = cythonize([
Extension("pytestpy", ["pytestpy.pyx"],
libraries=["pytest"],
)
]))
On Tuesday, 7 October 2014 at 22:46:09 UTC, Freddy wrote:
On Tuesday, 7 October 2014 at 20:55:59 UTC, Laeeth Isharc wrote:
Hi.
I am trying to create a shared library in D linked against
phobos so that I may use this in a cython extension module for
Python. Ultimately I would like to be able to use a D class
or struct (via the C++ interface) and call it from within
cython, since cython classes cannot be instantiated without
the gil (and this prevents easy parallelisation).
I feel a bit foolish asking the question as there is a nice
example here for working with plain C using dmd as the linker,
and using dmd and gcc to create a DMD shared library
statically linked to phobos. However, I have not succeeded in
creating a D library statically linked to phobos that works
with cython and python,
http://dlang.org/dll-linux.html#dso7
I tried it first with test C code to make sure I am able to
get the C library/cython/Python interaction working.
pytest.c:
#include <stdio.h>
long pytest(long a)
{
return a+1;
}
int main()
{
long a =pytest(100);
printf("%ld",a);
return 0;
}
pytestpy.pyx:
cdef extern long pytest(long a)
cpdef pytestpy():
return pytest(109)
setup.py:
from distutils.core import setup
from distutils.extension import Extension
from Cython.Build import cythonize
setup(
ext_modules = cythonize([
Extension("pytestpy", ["pytestpy.pyx"],
libraries=["pytest"],
)
]))
command line:
gcc -shared -o libpytest.so pytest.o
python setup.py build_ext -i
<copied libpytest.so to /usr/local/lib>
python
import pytestpy
pytestpy.pytestpy()
<it works>
----
now try pytest.d
import std.stdio;
extern (C) long pytest(long a)
{
return a*2;
}
void main()
{
auto a =pytest(100);
writefln("%d",a);
}
command line:
rm pytestd.o
rm libpytest.so
rm /usr/local/lib/libpytest.so
dmd -c pytest.d -fPIC
gcc -shared -o libpytest.so pytest.o -defaultlib=libphobos2.so
-L-rpath=/usr/local/lib
python
import pytestpy
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: /usr/local/lib/libpytest.so: undefined symbol:
_D3std5stdio12__ModuleInfoZ
I guess it is not linking to the D runtime, but I am not sure
what I should be doing to fix.
Any thoughts appreciated.
(The next step I was going to try when this works was C++
interface vs importing as a Cython class, but I thought best
to start simple).
I am running this on 64 bit Fedora 20.
Thanks.
Laeeth.
Since when does gcc have a -defaultlib option?
---
$ man gcc | grep defaultlib
object-file-name -llibrary -nostartfiles -nodefaultlibs
This is useful when you use -nostdlib or
-nodefaultlibs but you do
-nodefaultlibs is used.
-nodefaultlibs
-nodefaultlibs is libgcc.a, a library of internal
subroutines which
-nodefaultlibs you should usually specify -lgcc as
well. This
---
and why do you have a main function when compiling a shared
library?
Anyway, I think the problem is that "libpytest.so" can't find
"libphobos2.so". Try adding "libphobos2.so"'s location
(/usr/lib/x86_64-linux-gnu/libphobos2.so on my linux mint) to
your -rpath .
