From 6246b2aacb72c4b0971174b08c662fed7b32292f Mon Sep 17 00:00:00 2001
From: Bertho Stultiens <bertho@vagrearg.org>
Date: Sun, 28 Jun 2026 16:38:27 +0200
Subject: [PATCH] build: Select the libboost_python matching the python
 version.

---
 src/m4/ax_boost_python.m4 | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/src/m4/ax_boost_python.m4 b/src/m4/ax_boost_python.m4
index 28e35b62aa5..d5a4ab29022 100644
--- a/src/m4/ax_boost_python.m4
+++ b/src/m4/ax_boost_python.m4
@@ -93,7 +93,20 @@ BOOST_PYTHON_MODULE(test) { throw "Boost::Python test."; }]], [])],
 ])
 if test "$ac_cv_boost_python" = "yes"; then
   AC_DEFINE(HAVE_BOOST_PYTHON,,[define if the Boost::Python library is available])
-  ax_python_lib=boost_python
+  # Debian sid after trixie installs both libboost_python313 and
+  # libboost_python314 but it ships with Python 3.14. The detection loop fails
+  # to select to correct version and that results in a crash.
+  if test "x$ac_python_version" != "x"; then
+    # This is set in m4/ax_python_devel.m4
+    python_version=`echo $ac_python_version | tr -d .`
+  else
+    # Get the version from the binary and use it.
+    python_version=`$PYTHON_BIN -c 'import sys; print("{}{}".format(sys.version_info.major,sys.version_info.minor))'`
+  fi
+  # We use the original versionless test first and append a versioned one with
+  # the detected Python version to force the version matched library to be
+  # tested before any file-system located libraries.
+  ax_python_lib="boost_python boost_python$python_version"
   AC_ARG_WITH([boost-python],AS_HELP_STRING([--with-boost-python],[specify yes/no or the boost python library or suffix to use]),
   [if test "x$with_boost_python" != "xno" -a "x$with_boost_python" != "xyes"; then
      ax_python_lib=$with_boost_python