diff --git a/m17n-lib-c99.patch b/m17n-lib-c99.patch
new file mode 100644
index 0000000..d8158c9
--- /dev/null
+++ b/m17n-lib-c99.patch
@@ -0,0 +1,15 @@
+Submitted upstream: <https://savannah.nongnu.org/bugs/index.php?64106>
+
+diff --git a/example/medit.c b/example/medit.c
+index e6a6dc8c108fe44f..f2b109db3e0e2b81 100644
+--- a/example/medit.c
++++ b/example/medit.c
+@@ -662,7 +662,7 @@ static void MenuHelpProc (Widget, XEvent *, String *, Cardinal *);
+    off the current input method, otherwide turn on the input method
+    input_method_table[$IDX].  */
+ void
+-select_input_method (idx)
++select_input_method (int idx)
+ {
+   int previous_input_method = current_input_method;
+ 
diff --git a/m17n-lib.spec b/m17n-lib.spec
index 2b18554..d5d712a 100644
--- a/m17n-lib.spec
+++ b/m17n-lib.spec
@@ -7,7 +7,7 @@
 
 Name:           m17n-lib
 Version:        1.8.0
-Release:        15%{?dist}
+Release:        16%{?dist}
 Summary:        Multilingual text library
 
 License:        LGPL-2.1-or-later
@@ -15,6 +15,7 @@ URL:            http://www.nongnu.org/m17n/
 Source0:        http://download.savannah.gnu.org/releases/m17n/%{name}-%{version}.tar.gz
 Patch0:         %{name}-1.8.0-multilib.patch
 Patch1:         Fix-segmentation-fault-when-using-ibus-m17n-with-vi-telex-in-gedit-in-wayland.patch
+Patch2: m17n-lib-c99.patch
 
 BuildRequires: make
 BuildRequires:  m17n-db-devel libthai-devel
@@ -127,6 +128,9 @@ find %{buildroot} -name '*.la' -exec rm -f {} ';'
 %{_libdir}/libm17n-gui.so.*
 
 %changelog
+* Tue Apr 25 2023 Florian Weimer <fweimer@redhat.com> - 1.8.0-16
+- Fix C99 compatibility issue in example code
+
 * Thu Jan 19 2023 Fedora Release Engineering <releng@fedoraproject.org> - 1.8.0-15
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_38_Mass_Rebuild