diff --git a/foma-c99.patch b/foma-c99.patch
new file mode 100644
index 0000000..904700c
--- /dev/null
+++ b/foma-c99.patch
@@ -0,0 +1,33 @@
+Fix BOM_codes initializer
+
+Future compilers will reject the current initializer:
+
+io.c:1002:7: error: initialization of ‘char’ from ‘void *’ makes integer from pointer without a cast
+ 1002 |     { NULL, 0, NULL },
+      |       ^~~~
+io.c:1002:16: error: initialization of ‘char’ from ‘void *’ makes integer from pointer without a cast
+ 1002 |     { NULL, 0, NULL },
+      |                ^~~~
+io.c:996:26: warning: missing braces around initializer [-Wmissing-braces]
+  996 | static BOM BOM_codes[] = {
+      |                          ^
+io.c:996:26: warning: missing braces around initializer [-Wmissing-braces]
+
+The reason is that NULL is usually a pointer constant, which is not a
+valid expression for a character.
+
+Submitted upstream: <https://github.com/mhulden/foma/pull/151>
+
+diff --git a/foma/io.c b/foma/io.c
+index 5f6644419080df49..8fcaecb9c113758a 100644
+--- a/foma/io.c
++++ b/foma/io.c
+@@ -999,7 +999,7 @@ static BOM BOM_codes[] = {
+     { { 0x00, 0x00, 0xFE, 0xFF }, 4, "UTF-32BE" },
+     { { 0xFF, 0xFE }, 2, "UTF16-LE" },
+     { { 0xFE, 0xFF }, 2, "UTF16-BE" },
+-    { NULL, 0, NULL },
++    { { 0, } , 0, NULL },
+ };
+ 
+ BOM *check_BOM(char *buffer) {
diff --git a/foma.spec b/foma.spec
index ba06313..fb25469 100644
--- a/foma.spec
+++ b/foma.spec
@@ -9,7 +9,7 @@
 
 Name:           foma
 Version:        0.10.0
-Release:        0.7.%{snapshotdate}git%{shortcommit0}%{?dist}
+Release:        0.8.%{snapshotdate}git%{shortcommit0}%{?dist}
 Summary:        Xerox-compatible finite-state compiler
 
 License:        Apache-2.0
@@ -26,6 +26,7 @@ Source0:        https://github.com/mhulden/%{name}/archive/%{commit0}.tar.gz#/%{
 # the linker when building the shared library. For discussion on a similar
 # issue, see https://lists.debian.org/debian-devel/2016/05/msg00302.html
 Patch0:         foma-harden-build-fedora.patch
+Patch1: foma-c99.patch
 
 BuildRequires:  gcc zlib-devel readline-devel flex bison
 BuildRequires: make
@@ -104,6 +105,9 @@ find %{buildroot} -name '*.a' -exec rm -f {} ';'
 
 
 %changelog
+* Thu Jan 04 2024 Florian Weimer <fweimer@redhat.com> - 0.10.0-0.8.20210601gitdfe1ccb
+- Fix C compatibility issue
+
 * Mon Aug 21 2023 Parag Nemade <pnemade AT fedoraproject DOT org> - 0.10.0-0.7.20210601gitdfe1ccb
 - Migrate to SPDX license expression