diff --git a/kBuild-c99-2.patch b/kBuild-c99-2.patch
new file mode 100644
index 0000000..f4b291a
--- /dev/null
+++ b/kBuild-c99-2.patch
@@ -0,0 +1,16 @@
+The eval_buffer function expects the end of the string as the
+(optional) last argument, not its length.
+
+Index: src/kmk/loadapi.c
+===================================================================
+--- src/kmk/loadapi.c	(revision 3600)
++++ src/kmk/loadapi.c	(working copy)
+@@ -59,7 +59,7 @@
+   install_variable_buffer (&pbuf, &plen);
+ 
+   s = xstrdup (buffer);
+-  eval_buffer (s, flp IF_WITH_VALUE_LENGTH_PARAM (strlen (s) /** @todo suboptimal */));
++  eval_buffer (s, flp IF_WITH_VALUE_LENGTH_PARAM (s + strlen (s) /** @todo suboptimal */));
+   free (s);
+ 
+   restore_variable_buffer (pbuf, plen);
diff --git a/kBuild-c99.patch b/kBuild-c99.patch
new file mode 100644
index 0000000..bf35300
--- /dev/null
+++ b/kBuild-c99.patch
@@ -0,0 +1,158 @@
+Do not treat <strings.h> as an umbrella header for <string.h>
+The two are distinct on GNU/Linux.
+    
+Also add missing #include <string.h> in some files.
+
+Index: kbuild-0.1.9998svn3427/src/sed/lib/getline.c
+===================================================================
+--- kbuild-0.1.9998svn3427.orig/src/sed/lib/getline.c
++++ kbuild-0.1.9998svn3427/src/sed/lib/getline.c
+@@ -9,10 +9,10 @@
+ #include <stdio.h>
+ #undef getline 			/* bird */
+ 
++#include <string.h>
++
+ #ifdef HAVE_STRINGS_H
+ # include <strings.h>
+-#else
+-# include <string.h>
+ #endif /* HAVE_STRINGS_H */
+ 
+ #ifdef HAVE_STDLIB_H
+Index: kbuild-0.1.9998svn3427/src/sed/lib/mkstemp.c
+===================================================================
+--- kbuild-0.1.9998svn3427.orig/src/sed/lib/mkstemp.c
++++ kbuild-0.1.9998svn3427/src/sed/lib/mkstemp.c
+@@ -2,10 +2,10 @@
+ #include "config.h"
+ #endif
+ 
++#include <string.h>
++
+ #ifdef HAVE_STRINGS_H
+ # include <strings.h>
+-#else
+-# include <string.h>
+ #endif /* HAVE_STRINGS_H */
+ 
+ #ifdef HAVE_STDLIB_H
+Index: kbuild-0.1.9998svn3427/src/sed/lib/utils.c
+===================================================================
+--- kbuild-0.1.9998svn3427.orig/src/sed/lib/utils.c
++++ kbuild-0.1.9998svn3427/src/sed/lib/utils.c
+@@ -19,16 +19,17 @@
+ #include "config.h"
+ 
+ #include <stdio.h>
++#include <unistd.h>
+ 
+ #include <errno.h>
+ #ifndef errno
+   extern int errno;
+ #endif
+ 
++#include <string.h>
++
+ #ifdef HAVE_STRINGS_H
+ # include <strings.h>
+-#else
+-# include <string.h>
+ #endif /* HAVE_STRINGS_H */
+ 
+ #ifdef HAVE_STDLIB_H
+Index: kbuild-0.1.9998svn3427/src/sed/sed/compile.c
+===================================================================
+--- kbuild-0.1.9998svn3427.orig/src/sed/sed/compile.c
++++ kbuild-0.1.9998svn3427/src/sed/sed/compile.c
+@@ -22,14 +22,13 @@
+ #include "strverscmp.h"
+ #include <stdio.h>
+ #include <ctype.h>
++#include <string.h>
+ 
+ #ifdef HAVE_STRINGS_H
+ # include <strings.h>
+ # ifdef HAVE_MEMORY_H
+ #  include <memory.h>
+ # endif
+-#else
+-# include <string.h>
+ #endif /* HAVE_STRINGS_H */
+ 
+ #ifdef HAVE_STDLIB_H
+Index: kbuild-0.1.9998svn3427/src/sed/sed/execute.c
+===================================================================
+--- kbuild-0.1.9998svn3427.orig/src/sed/sed/execute.c
++++ kbuild-0.1.9998svn3427/src/sed/sed/execute.c
+@@ -24,6 +24,7 @@
+ 
+ #include <stdio.h>
+ #include <ctype.h>
++#include <string.h>
+ 
+ #include <errno.h>
+ #ifndef errno
+@@ -46,8 +47,6 @@ extern int errno;
+ 
+ #ifdef HAVE_STRINGS_H
+ # include <strings.h>
+-#else
+-# include <string.h>
+ #endif /*HAVE_STRINGS_H*/
+ #ifdef HAVE_MEMORY_H
+ # include <memory.h>
+Index: kbuild-0.1.9998svn3427/src/sed/sed/fmt.c
+===================================================================
+--- kbuild-0.1.9998svn3427.orig/src/sed/sed/fmt.c
++++ kbuild-0.1.9998svn3427/src/sed/sed/fmt.c
+@@ -22,6 +22,7 @@
+ #include <stdio.h>
+ #include <ctype.h>
+ #include <sys/types.h>
++#include <string.h>
+ 
+ #if HAVE_LIMITS_H
+ # include <limits.h>
+Index: kbuild-0.1.9998svn3427/src/sed/sed/mbcs.c
+===================================================================
+--- kbuild-0.1.9998svn3427.orig/src/sed/sed/mbcs.c
++++ kbuild-0.1.9998svn3427/src/sed/sed/mbcs.c
+@@ -17,6 +17,7 @@
+ 
+ #include "sed.h"
+ #include <stdlib.h>
++#include <string.h>
+ 
+ int mb_cur_max;
+ 
+Index: kbuild-0.1.9998svn3427/src/sed/sed/regexp.c
+===================================================================
+--- kbuild-0.1.9998svn3427.orig/src/sed/sed/regexp.c
++++ kbuild-0.1.9998svn3427/src/sed/sed/regexp.c
+@@ -19,6 +19,7 @@
+ 
+ #include <ctype.h>
+ #include <stdio.h>
++#include <string.h>
+ #ifdef HAVE_STDLIB_H
+ # include <stdlib.h>
+ #endif
+Index: kbuild-0.1.9998svn3427/src/sed/sed/sed.c
+===================================================================
+--- kbuild-0.1.9998svn3427.orig/src/sed/sed/sed.c
++++ kbuild-0.1.9998svn3427/src/sed/sed/sed.c
+@@ -22,12 +22,10 @@
+ 
+ #include "sed.h"
+ 
+-
+ #include <stdio.h>
++#include <string.h>
+ #ifdef HAVE_STRINGS_H
+ # include <strings.h>
+-#else
+-# include <string.h>
+ #endif /*HAVE_STRINGS_H*/
+ #ifdef HAVE_MEMORY_H
+ # include <memory.h>
diff --git a/kBuild-configure-c99-2.patch b/kBuild-configure-c99-2.patch
new file mode 100644
index 0000000..722c457
--- /dev/null
+++ b/kBuild-configure-c99-2.patch
@@ -0,0 +1,12 @@
+Index: kbuild-0.1.9998svn3427/src/kmk/configure.ac
+===================================================================
+--- kbuild-0.1.9998svn3427.orig/src/kmk/configure.ac
++++ kbuild-0.1.9998svn3427/src/kmk/configure.ac
+@@ -121,6 +121,7 @@ pds_AC_DOS_PATHS
+ AC_CACHE_CHECK([for standard gettimeofday], [ac_cv_func_gettimeofday],
+   [ac_cv_func_gettimeofday=no
+    AC_RUN_IFELSE([AC_LANG_SOURCE([[#include <sys/time.h>
++                  #include <stdlib.h>
+                   int main ()
+                   {
+                     struct timeval t; t.tv_sec = -1; t.tv_usec = -1;
diff --git a/kBuild-configure-c99.patch b/kBuild-configure-c99.patch
new file mode 100644
index 0000000..36d3f9d
--- /dev/null
+++ b/kBuild-configure-c99.patch
@@ -0,0 +1,48 @@
+Fix some typical C99 compatibility issues in old configure scripts.
+
+diff --git a/src/sed/config/getline.m4 b/src/sed/config/getline.m4
+index ff8b5f4b..52d2e3e7 100644
+--- a/src/sed/config/getline.m4
++++ b/src/sed/config/getline.m4
+@@ -27,7 +27,7 @@ AC_DEFUN([AM_FUNC_GETLINE],
+       if (!in)
+ 	return 1;
+       len = getline (&line, &siz, in);
+-      exit ((len == 4 && line && strcmp (line, "foo\n") == 0) ? 0 : 1);
++      return (len == 4 && line && strcmp (line, "foo\n") == 0) ? 0 : 1;
+     }
+     ], am_cv_func_working_getline=yes dnl The library version works.
+     , am_cv_func_working_getline=no dnl The library version does NOT work.
+diff --git a/src/sed/configure b/src/sed/configure
+index 0b01618f..b1172113 100755
+--- a/src/sed/configure
++++ b/src/sed/configure
+@@ -2593,7 +2593,7 @@ if { (eval echo "$as_me:$LINENO: \"$ac_compile\"") >&5
+   echo "$as_me:$LINENO: \$? = $ac_status" >&5
+   (exit $ac_status); }; }; then
+   for ac_declaration in \
+-   '' \
++   '#include <stdlib.h>' \
+    'extern "C" void std::exit (int) throw (); using std::exit;' \
+    'extern "C" void std::exit (int); using std::exit;' \
+    'extern "C" void exit (int) throw ();' \
+@@ -3378,8 +3378,8 @@ main ()
+   for (i = 0; i < 256; i++)
+     if (XOR (islower (i), ISLOWER (i))
+ 	|| toupper (i) != TOUPPER (i))
+-      exit(2);
+-  exit (0);
++      return 2;
++  return 0;
+ }
+ _ACEOF
+ rm -f conftest$ac_exeext
+@@ -5747,7 +5747,7 @@ cat >>conftest.$ac_ext <<_ACEOF
+       if (!in)
+ 	return 1;
+       len = getline (&line, &siz, in);
+-      exit ((len == 4 && line && strcmp (line, "foo\n") == 0) ? 0 : 1);
++      return (len == 4 && line && strcmp (line, "foo\n") == 0) ? 0 : 1;
+     }
+ 
+ _ACEOF
diff --git a/kbuild.changes b/kbuild.changes
index 8d947c5..2bbd6fd 100644
--- a/kbuild.changes
+++ b/kbuild.changes
@@ -1,3 +1,14 @@
+-------------------------------------------------------------------
+Fri Jun  7 11:04:30 UTC 2024 - Martin Jambor <mjambor@suse.com>
+
+- Make kbuild buildable with GCC 14 (boo#1225792)
+  * Changes to configure machinery so that it does not fail and detect
+    what it has detected with previous GCC versions.
+    (kBuild-configure-c99.patch, kBuild-configure-c99-2.patch)
+  * Add many missing includes (kBuild-c99.patch).
+  * Fix an actual bug in a call to eval_buffer that also manifests as
+    a C99 violation (kBuild-c99-2.patch).
+
 -------------------------------------------------------------------
 Thu Feb 22 12:41:22 UTC 2024 - Dominique Leuenberger <dimstar@opensuse.org>
 
diff --git a/kbuild.spec b/kbuild.spec
index 8a8192f..4156006 100644
--- a/kbuild.spec
+++ b/kbuild.spec
@@ -1,7 +1,7 @@
 #
 # spec file for package kbuild
 #
-# Copyright (c) 2020 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
@@ -34,6 +34,17 @@ Patch8:         kbuild-wrong-memset.patch
 Patch9:         ppc64le.patch
 Patch10:        aarch64.patch
 Patch13:        glob-lstat.patch
+
+# C99 compatibility patches to resolve boo#1225792:
+# From from https://bugzilla.redhat.com/show_bug.cgi?id=2154544
+Patch14:        kBuild-configure-c99.patch
+# Somehow RedHat did not need this one:
+Patch15:        kBuild-configure-c99-2.patch
+# From from https://bugzilla.redhat.com/show_bug.cgi?id=2154544
+Patch16:        kBuild-c99.patch
+# From from https://bugzilla.redhat.com/show_bug.cgi?id=2154544
+Patch17:        kBuild-c99-2.patch
+
 BuildRequires:  automake
 BuildRequires:  bison
 BuildRequires:  byacc
@@ -66,6 +77,10 @@ The goals of the kBuild framework:
 %patch -P 9 -p1
 %patch -P 10 -p1
 %patch -P 13 -p1
+%patch -P 14 -p1
+%patch -P 15 -p1
+%patch -P 16 -p1
+%patch -P 17 -p0
 
 %build
 export CFLAGS="%{optflags} -fno-strict-aliasing"