https://bugs.gentoo.org/898970
--- a/configure.in
+++ b/configure.in
@@ -186,7 +186,8 @@ AC_CACHE_VAL(lrzsz_cv_sys_ftime_ok,
 #include <sys/types.h>
 #include <sys/timeb.h>
 #include <stdio.h>
-main ()
+#include <stdlib.h>
+int main (void)
 {
   struct timeb s, slast;
   int c = 0;