Index: prelink-4c79120bcdbde0616f592458ccde7035e92ca3d8/m4/libelf.m4
===================================================================
--- prelink-4c79120bcdbde0616f592458ccde7035e92ca3d8.orig/m4/libelf.m4
+++ prelink-4c79120bcdbde0616f592458ccde7035e92ca3d8/m4/libelf.m4
@@ -14,6 +14,7 @@ AC_DEFUN(AC_LIBELF_SXWORD,
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
+#include <unistd.h>
 
 static unsigned char sparc64_elf[] = {
 0x7f,0x45,0x4c,0x46,0x02,0x02,0x01,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,