Taken from https://bugs.gentoo.org/show_bug.cgi?id=544610
--- a/makedefs	2015-03-27 00:25:29.103726341 +0100
+++ a/makedefs	2015-03-27 00:32:14.657061042 +0100
@@ -500,7 +500,8 @@ 
 		: ${SHLIB_ENV="LD_LIBRARY_PATH=`pwd`/lib"}
 		: ${PLUGIN_LD="${CC-gcc} -shared"}
 		;;
-    Linux.3*)	SYSTYPE=LINUX3
+    Linux.*)
+		SYSTYPE=LINUX
 		case "$CCARGS" in
 		 *-DNO_DB*) ;;
 		 *-DHAS_DB*) ;;
--- a/src/util/sys_defs.h	2015-03-27 00:36:21.203728543 +0100
+++ a/src/util/sys_defs.h	2015-03-27 00:36:09.657061839 +0100
@@ -756,7 +756,7 @@ 
  /*
   * LINUX.
   */
+#if defined(LINUX2) || defined(LINUX)
-#if defined(LINUX2) || defined(LINUX3)
 #define SUPPORTED
 #include <sys/types.h>
 #define UINT32_TYPE	unsigned int
