[RFC] configure additions for linking with static libpython

[RFC] configure additions for linking with static libpython

[Doug Evans]

Hi.
I was going through my mail and found this thread:

http://sourceware.org/ml/gdb/2010-01/msg00223.html

Tested on i686-linux and amd64-linux with a static-library-only
python installation.  I wasn't sure how common static-only
installations are so I didn't submitted this earlier.

The -lutil is necessary to find forkpty, openpty,
referenced by at least libpython2.4.a(posixmodule.o).
I don't know how common libutil is w.r.t. libpython.
Maybe the script should first test for libutil?

2010-02-08  Doug Evans  <dje@google.com>

	* configure.ac (--with-python): Add necessary libraries
	-dl, -lpthread, -lutil in case linking with libpython.a.
	Add attempt to find libpython.a.
	* configure: Regenerated.

Index: configure.ac
===================================================================
RCS file: /cvs/src/src/gdb/configure.ac,v
retrieving revision 1.114
diff -u -p -r1.114 configure.ac
--- configure.ac	25 Jan 2010 13:22:02 -0000	1.114
+++ configure.ac	8 Feb 2010 19:08:11 -0000
@@ -595,7 +595,7 @@ AC_DEFUN([AC_TRY_LIBPYTHON],
   [HAVE_LIB]VERSION=no
   AC_MSG_CHECKING([for ${version}])
   save_LIBS=$LIBS
-  LIBS="$LIBS -l${version}"
+  LIBS="$LIBS -l${version} -ldl -lpthread -lutil"
   AC_LINK_IFELSE(AC_LANG_PROGRAM([[#include "${version}/Python.h"]],
                                  [[Py_Initialize ();]]),
                  [[HAVE_LIB]VERSION=yes
@@ -623,6 +623,11 @@ else
   /*)
     python_includes="-I${with_python}/include"
     python_libs="-L${with_python}/lib"
+    # This one is to find libpythonx.y.a
+    python_config_dir=`echo ${with_python}/lib/python*.*/config`
+    if test -d "${python_config_dir}"; then
+      python_libs="${python_libs} -L${python_config_dir}"
+    fi
     ;;
   *)
     AC_ERROR(invalid value for --with-python)

Re: [RFC] configure additions for linking with static libpython

[Daniel Jacobowitz]

On Mon, Feb 08, 2010 at 11:25:38AM -0800, Doug Evans wrote:
> Hi.
> I was going through my mail and found this thread:
> 
> http://sourceware.org/ml/gdb/2010-01/msg00223.html
> 
> Tested on i686-linux and amd64-linux with a static-library-only
> python installation.  I wasn't sure how common static-only
> installations are so I didn't submitted this earlier.
> 
> The -lutil is necessary to find forkpty, openpty,
> referenced by at least libpython2.4.a(posixmodule.o).
> I don't know how common libutil is w.r.t. libpython.
> Maybe the script should first test for libutil?

Yes, I think it should.  Can we check for all three libraries
and link any that work?

-- 
Daniel Jacobowitz
CodeSourcery

Re: [RFC] configure additions for linking with static libpython

[Joel Brobecker]

> 2010-02-08  Doug Evans  <dje@google.com>
> 
> 	* configure.ac (--with-python): Add necessary libraries
> 	-dl, -lpthread, -lutil in case linking with libpython.a.
> 	Add attempt to find libpython.a.
> 	* configure: Regenerated.

I don't object if this is useful to anyone, but...

I am wondering whether it is really useful to link GDB against
libpython.a... I looked at the thread you referenced, and I still
wasn't sure what the problem was... Linking GDB against a static
libpython is something I thought about for AdaCore, but I also
realized that we'd need to distribute the python .py files anyway,
so it's not big deal to distribute the entire python install, including
share SOs...

-- 
Joel