updated for version 7.4.253

Problem:    Crash when using cpp syntax file with pattern using external
	    match. (Havard Garnes)
Solution:   Discard match when end column is before start column.

Author: brammool

src/regexp.c

@@ -4146,7 +4146,8 @@ regtry(prog, col)
 	    {
 		/* Only accept single line matches. */
 		if (reg_startzpos[i].lnum >= 0
-			&& reg_endzpos[i].lnum == reg_startzpos[i].lnum)
+			&& reg_endzpos[i].lnum == reg_startzpos[i].lnum
+			&& reg_endzpos[i].col >= reg_startzpos[i].col)
 		    re_extmatch_out->matches[i] =
 			vim_strnsave(reg_getline(reg_startzpos[i].lnum)
 						       + reg_startzpos[i].col,

src/regexp_nfa.c

@@ -6781,8 +6781,10 @@ nfa_regtry(prog, col)
 	    {
 		struct multipos *mpos = &subs.synt.list.multi[i];
 
-		/* Only accept single line matches. */
-		if (mpos->start.lnum >= 0 && mpos->start.lnum == mpos->end.lnum)
+		/* Only accept single line matches that are valid. */
+		if (mpos->start.lnum >= 0
+			&& mpos->start.lnum == mpos->end.lnum
+			&& mpos->end.col >= mpos->start.col)
 		    re_extmatch_out->matches[i] =
 			vim_strnsave(reg_getline(mpos->start.lnum)
 							    + mpos->start.col,

src/version.c

@@ -734,6 +734,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    253,
 /**/
     252,
 /**/