patch 9.0.1225: reading past the end of a line when formatting text

Problem:    Reading past the end of a line when formatting text.
Solution:   Check for not going over the end of the line.

src/textformat.c

@@ -540,6 +540,9 @@ same_leader(
     if (leader1_len == 0)
 	return (leader2_len == 0);
 
+    char_u  *lnum_line = NULL;
+    int	    line_len = 0;
+
     // If first leader has 'f' flag, the lines can be joined only if the
     // second line does not have a leader.
     // If first leader has 'e' flag, the lines can never be joined.
@@ -555,7 +558,12 @@ same_leader(
 		return FALSE;
 	    if (*p == COM_START)
 	    {
-		if (*(ml_get(lnum) + leader1_len) == NUL)
+		if (lnum_line == NULL)
+		{
+		    lnum_line = ml_get(lnum);
+		    line_len = (int)STRLEN(lnum_line);
+		}
+		if (line_len <= leader1_len)
 		    return FALSE;
 		if (leader2_flags == NULL || leader2_len == 0)
 		    return FALSE;

src/version.c

@@ -695,6 +695,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1225,
 /**/
     1224,
 /**/