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.
diff --git a/src/option.h b/src/option.h
index e962ba3..cf7ba04 100644
--- a/src/option.h
+++ b/src/option.h
@@ -463,7 +463,7 @@
 #define DY_LASTLINE		0x001
 #define DY_UHEX			0x002
 EXTERN int	p_ed;		/* 'edcompatible' */
-#ifdef FEAT_VERTSPLIT
+#ifdef FEAT_WINDOWS
 EXTERN char_u	*p_ead;		/* 'eadirection' */
 #endif
 EXTERN int	p_ea;		/* 'equalalways' */
@@ -802,7 +802,7 @@
 #ifdef FEAT_SPELL
 EXTERN char_u	*p_sps;		/* 'spellsuggest' */
 #endif
-#ifdef FEAT_VERTSPLIT
+#ifdef FEAT_WINDOWS
 EXTERN int	p_spr;		/* 'splitright' */
 #endif
 EXTERN int	p_sol;		/* 'startofline' */
@@ -957,8 +957,6 @@
 #ifdef FEAT_WINDOWS
 EXTERN long	p_wh;		/* 'winheight' */
 EXTERN long	p_wmh;		/* 'winminheight' */
-#endif
-#ifdef FEAT_VERTSPLIT
 EXTERN long	p_wmw;		/* 'winminwidth' */
 EXTERN long	p_wiw;		/* 'winwidth' */
 #endif
@@ -1172,8 +1170,6 @@
 #endif
 #ifdef FEAT_WINDOWS
     , WV_WFH
-#endif
-#ifdef FEAT_VERTSPLIT
     , WV_WFW
 #endif
     , WV_WRAP