diff --git a/src/main.c b/src/main.c
index 83e55d1..35c940f 100644
--- a/src/main.c
+++ b/src/main.c
@@ -2088,7 +2088,7 @@
 		break;
 
 		case 'O':	/* "-O[N]" open N vertical split windows */
-#if defined(FEAT_VERTSPLIT) && defined(FEAT_WINDOWS)
+#ifdef FEAT_WINDOWS
 		/* default is 0: open window for each file */
 		parmp->window_count = get_number_arg((char_u *)argv[0],
 								&argv_idx, 0);