commit 44a2f923c00f1384c9ecde12fb5b4711bc20702e
author Bram Moolenaar <Bram@vim.org> Sat Mar 19 22:11:51 2016 +0100
committer Bram Moolenaar <Bram@vim.org> Sat Mar 19 22:11:51 2016 +0100
tree ff48a0f263f488b023e5b4c7d45af05dade92e8f
parent cc6cf9b9f9045a7d8b5923ea0c556e9a4c2567d3

patch 7.4.1611
Problem:    The versplit feature makes the code uneccessary complicated.
Solution:   Remove FEAT_VERTSPLIT, always support vertical splits when
            FEAT_WINDOWS is defined.

src/main.c

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);