Hi, I build gdb on Linux with a statically embedded libpython.a rather than the recommanded .so way. It seems like the resulting gdb fails to load any module using dynamic link, like for example "import math". It's clear that the "problem" is the fact of using -rdynamic vs --dynamic-list. Actually this "problem" was fixed a long time ago, and we can see in configure.ac something like: AC_RUN_IFELSE( [AC_LANG_PROGRAM( [#include "Python.h"], [int err; Py_Initialize (); err = PyRun_SimpleString ("import itertools\n"); Py_Finalize (); return err == 0 ? 0 : 1;])], [dynamic_list=true], [], [true]) to check whether python can import something without "-rdynamic". However with python 3 (at least in my case it was python 3.9, but I could also check with another python 3.4 that it was also the case) itertools seems to be a builtin, so doesn't actually load any.so. Do you think this "import itertools" shall be replaced by another module which we know is a real dynamic python module on both python 2 and python 3 ? I propose to replace it by "import ctypes" instead which seems to be a modules in both major python releases. Cheers, Romain
FYI: I tested the following patch, which worked for me (I tested only a statically linked libpython, using python 3.9 and gdb 10 on Linux): --- gdb/configure +++ gdb/configure @@ -16159,7 +16159,7 @@ { int err; Py_Initialize (); - err = PyRun_SimpleString ("import itertools\n"); + err = PyRun_SimpleString ("import ctypes\n"); Py_Finalize (); return err == 0 ? 0 : 1; ; --- gdb/configure.ac +++ gdb/configure.ac @@ -1599,7 +1599,7 @@ [#include "Python.h"], [int err; Py_Initialize (); - err = PyRun_SimpleString ("import itertools\n"); + err = PyRun_SimpleString ("import ctypes\n"); Py_Finalize (); return err == 0 ? 0 : 1;])], [dynamic_list=true], [], [true]) Cheers, Romain
Thanks. Note that we don't do patch review on Bugzilla, so if you'd like your patch to be considered for merging, please send it to the gdb-patches mailing list following the guidelines here: https://sourceware.org/gdb/wiki/ContributionChecklist
The master branch has been updated by Andrew Burgess <aburgess@sourceware.org>: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=3fed4c0b7adeae7b2bfd9aa59818bb8f3f381031 commit 3fed4c0b7adeae7b2bfd9aa59818bb8f3f381031 Author: Romain Geissler <romain.geissler@amadeus.com> Date: Fri Nov 6 17:47:21 2020 +0000 gdb: better static python detection in configure machinery In python 3, itertools is a builtin module, so whether or not the python you link against is a shared or a static one, importing it works. Change the import test to use ctypes which is a dynamic module in both python 2 and 3. gdb/ChangeLog: PR python/26832 * configure: Regenerate. * configure.ac: Check for python modules ctypes instead of itertools.
The gdb-10-branch branch has been updated by Andrew Burgess <aburgess@sourceware.org>: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=60714c0fc0cc7cc873440b4b9362c11f28daf585 commit 60714c0fc0cc7cc873440b4b9362c11f28daf585 Author: Romain Geissler <romain.geissler@amadeus.com> Date: Fri Nov 6 17:47:21 2020 +0000 gdb: better static python detection in configure machinery In python 3, itertools is a builtin module, so whether or not the python you link against is a shared or a static one, importing it works. Change the import test to use ctypes which is a dynamic module in both python 2 and 3. gdb/ChangeLog: PR python/26832 * configure: Regenerate. * configure.ac: Check for python modules ctypes instead of itertools.
Fixed in the master branch + cherry-picked in the gdb 10 branch.