Silence some whining

test/stdlib/ptytest.c

@@ -1,3 +1,4 @@
+#define _XOPEN_SOURCE
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>

test/stdlib/testatexit.c

@@ -69,6 +69,7 @@ main ( void )
 		i = (i+1) % numfuncs;
 	}
 	printf("%d functions registered with atexit.\n", count);
-	/* implicit exit */
+
+	return 0;
 }