diff --git a/sane-backends-1.2.1-fedora-c99.patch b/sane-backends-1.2.1-fedora-c99.patch
new file mode 100644
index 0000000..70303ab
--- /dev/null
+++ b/sane-backends-1.2.1-fedora-c99.patch
@@ -0,0 +1,72 @@
+From 300b460970f538ab515835f14650785e88808a8f Mon Sep 17 00:00:00 2001
+From: Sam James <sam@gentoo.org>
+Date: Fri, 4 Nov 2022 04:04:46 +0000
+Subject: acinclude.m4: fix -Wimplicit-function-declaration
+
+-Wimplicit-function-declaration will become an error by default
+in Clang 16.
+
+Fixes errors like:
+```
+error: call to undeclared library function 'exit' with type 'void (int) __attribute__((noreturn))'; ISO C99 and later do not support implicit function declarations [-Werror,-Wimplicit-function-declaration]
+```
+
+Signed-off-by: Sam James <sam@gentoo.org>
+
+DJ: Added pre-configure'd configure
+
+diff --git a/acinclude.m4 b/acinclude.m4
+index df8abe148..71e22c8d4 100644
+--- a/acinclude.m4
++++ b/acinclude.m4
+@@ -471,6 +471,7 @@ AC_DEFUN([SANE_CHECK_IPV6],
+   if test "$ipv6" != "no" ; then
+     AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
+ 	#define INET6
++	#include <stdlib.h>
+ 	#include <sys/types.h>
+ 	#include <sys/socket.h> ]], [[
+ 	 /* AF_INET6 available check */
+@@ -492,6 +493,7 @@ AC_DEFUN([SANE_CHECK_IPV6],
+     AC_MSG_CHECKING([whether struct sockaddr_storage has an ss_family member])
+     AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
+ 	#define INET6
++	#include <stdlib.h>
+ 	#include <sys/types.h>
+ 	#include <sys/socket.h> ]], [[
+ 	/* test if the ss_family member exists in struct sockaddr_storage */
+@@ -504,6 +506,7 @@ AC_DEFUN([SANE_CHECK_IPV6],
+     ], [
+ 		AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
+ 		#define INET6
++		#include <stdlib.h>
+ 		#include <sys/types.h>
+ 		#include <sys/socket.h> ]], [[
+ 		/* test if the __ss_family member exists in struct sockaddr_storage */
+diff -rup a/configure b/configure
+--- a/configure	2023-02-05 21:12:47.000000000 -0500
++++ b/configure	2023-02-20 21:21:46.496776406 -0500
+@@ -25824,6 +25824,7 @@ fi
+ /* end confdefs.h.  */
+ 
+ 	#define INET6
++	#include <stdlib.h>
+ 	#include <sys/types.h>
+ 	#include <sys/socket.h>
+ int
+@@ -25866,6 +25867,7 @@ $as_echo_n "checking whether struct sock
+ /* end confdefs.h.  */
+ 
+ 	#define INET6
++	#include <stdlib.h>
+ 	#include <sys/types.h>
+ 	#include <sys/socket.h>
+ int
+@@ -25895,6 +25897,7 @@ else
+ /* end confdefs.h.  */
+ 
+ 		#define INET6
++		#include <stdlib.h>
+ 		#include <sys/types.h>
+ 		#include <sys/socket.h>
+ int
diff --git a/sane-backends.spec b/sane-backends.spec
index d98083e..aea1b8c 100644
--- a/sane-backends.spec
+++ b/sane-backends.spec
@@ -18,7 +18,7 @@
 Summary: Scanner access software
 Name: sane-backends
 Version: 1.2.1
-Release: 1%{?dist}
+Release: 2%{?dist}
 # lib/ is LGPLv2+, backends are GPLv2+ with exceptions
 # Tools are GPLv2+, docs are public domain
 # see LICENSE for details
@@ -43,6 +43,8 @@ Patch2: sane-backends-1.0.23-sane-config-multilib.patch
 # 2139882 - Plustek 8100 scanner not detected
 # sent upstream as https://gitlab.com/sane-project/backends/-/merge_requests/767
 Patch3: sane-genesys-plustek7600i-8100-support.patch
+# Fix for c99
+Patch4: sane-backends-1.2.1-fedora-c99.patch
 
 URL: http://www.sane-project.org
 
@@ -164,6 +166,8 @@ access image acquisition devices available on the local host.
 
 %prep
 %autosetup -S git
+# To avoid needing to run aclocal et al
+touch -r acinclude.m4 aclocal.m4 configure Makefile.in
 
 %build
 CFLAGS="%optflags -fno-strict-aliasing"
@@ -386,6 +390,9 @@ udevadm hwdb --update >/dev/null 2>&1 || :
 %{_unitdir}/saned@.service
 
 %changelog
+* Tue Feb 21 2023 DJ Delorie <dj@redhat.com> - 1.2.1-2
+- Fix C99 compatibility issue
+
 * Fri Feb 17 2023 Zdenek Dohnal <zdohnal@redhat.com> - 1.2.1-1
 - 2167250 - sane-backends-1.2.1 is available