updated for version 7.3.840
Problem:    "\@<!" in regexp does not work correctly with multi-byte
            characters, especially cp932.
Solution:   Move column to start of multi-byte character. (Yasuhiro Matsumoto)
diff --git a/src/regexp.c b/src/regexp.c
index d85ded8..6ecb6dd 100644
--- a/src/regexp.c
+++ b/src/regexp.c
@@ -5449,6 +5449,13 @@
 			}
 		    }
 		    else
+#ifdef FEAT_MBYTE
+		    if (has_mbyte)
+			rp->rs_un.regsave.rs_u.pos.col -=
+			    (*mb_head_off)(regline, regline
+				    + rp->rs_un.regsave.rs_u.pos.col - 1) + 1;
+		    else
+#endif
 			--rp->rs_un.regsave.rs_u.pos.col;
 		}
 		else
diff --git a/src/version.c b/src/version.c
index 95cea6a..7c12188 100644
--- a/src/version.c
+++ b/src/version.c
@@ -729,6 +729,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    840,
+/**/
     839,
 /**/
     838,