Use gfc_charlen_t instead of int in gfc_conv_string_init

Committed as obvious.

2018-01-31  Janne Blomqvist  <jb@gcc.gnu.org>

        * trans-const.c (gfc_conv_string_init): Use gfc_charlen_t instead
        of int for slen.

From-SVN: r257258

gcc/fortran/ChangeLog

 2018-01-31  Janne Blomqvist  <jb@gcc.gnu.org>
 
+	* trans-const.c (gfc_conv_string_init): Use gfc_charlen_t instead
+	of int for slen.
+
+2018-01-31  Janne Blomqvist  <jb@gcc.gnu.org>
+
 	PR fortran/78534
 	* trans-expr.c (fill_with_spaces): Use memset instead of
 	generating loop.

gcc/fortran/trans-const.c

@@ -141,7 +141,7 @@ gfc_conv_string_init (tree length, gfc_expr * expr)
 {
   gfc_char_t *s;
   HOST_WIDE_INT len;
-  int slen;
+  gfc_charlen_t slen;
   tree str;
   bool free_s = false;