diff --git a/159.patch b/159.patch
new file mode 100644
index 0000000..00e0434
--- /dev/null
+++ b/159.patch
@@ -0,0 +1,28 @@
+From df2857fff3c492692ca09f31699972970042bc07 Mon Sep 17 00:00:00 2001
+From: Michael Karcher <github@mkarcher.dialup.fu-berlin.de>
+Date: Wed, 12 Jun 2024 22:42:45 +0200
+Subject: [PATCH] Define _POSIX_C_SOURCE for crfsuite source files
+
+gcc-14 has "-Werror=implicit-function-declaration" enabled by default.
+crfsuite uses posix_memalign which only gets defined when _POSIX_C_SOURCE is
+defined, so make sure the flag is set when compiling crfsuite.
+
+On the other hand, openSUSE Tumbleweed has _POSIX_C_SOURCE defined
+in pyconfig.h, so you must not add "-D_POSIX_C_SOURCE" when compiling
+the python binding source code. So add it only for the subdir crfsuite.
+---
+ setup.py | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/setup.py b/setup.py
+index 8036363..f0dc370 100755
+--- a/setup.py
++++ b/setup.py
+@@ -30,6 +30,7 @@ def build_extensions(self):
+         _compile = c._compile
+ 
+         def c_compile(obj, src, ext, cc_args, extra_postargs, pp_opts):
++            cc_args = cc_args + ['-D_POSIX_C_SOURCE=200112L'] if src.startswith('crfsuite/') else cc_args
+             cc_args = cc_args + ['-std=c99'] if src.endswith('.c') else cc_args
+             return _compile(obj, src, ext, cc_args, extra_postargs, pp_opts)
+ 
diff --git a/python-python-crfsuite.changes b/python-python-crfsuite.changes
index 5006408..b854cba 100644
--- a/python-python-crfsuite.changes
+++ b/python-python-crfsuite.changes
@@ -1,3 +1,9 @@
+-------------------------------------------------------------------
+Wed Jun 12 21:37:57 UTC 2024 - John Paul Adrian Glaubitz <adrian.glaubitz@suse.com>
+
+- Cherry-pick upstream patch to fix build with GCC 14
+  * https://github.com/scrapinghub/python-crfsuite/pull/159.patch
+
 -------------------------------------------------------------------
 Tue Dec 26 20:26:15 UTC 2023 - Dirk Müller <dmueller@suse.com>
 
diff --git a/python-python-crfsuite.spec b/python-python-crfsuite.spec
index 807452d..77ddc90 100644
--- a/python-python-crfsuite.spec
+++ b/python-python-crfsuite.spec
@@ -1,7 +1,7 @@
 #
 # spec file for package python-python-crfsuite
 #
-# Copyright (c) 2023 SUSE LLC
+# Copyright (c) 2024 SUSE LLC
 #
 # All modifications and additions to the file contributed by third parties
 # remain the property of their copyright owners, unless otherwise agreed
@@ -25,6 +25,8 @@ License:        MIT
 Group:          Development/Languages/Python
 URL:            https://github.com/scrapinghub/python-crfsuite
 Source:         https://files.pythonhosted.org/packages/source/p/python-crfsuite/python-crfsuite-%{version}.tar.gz
+# PATCH-FIX-UPSTREAM - Define _POSIX_C_SOURCE for crfsuite source files
+Patch:          https://github.com/scrapinghub/python-crfsuite/pull/159.patch
 BuildRequires:  %{python_module devel}
 BuildRequires:  %{python_module pytest}
 BuildRequires:  %{python_module setuptools}