Use ptrdiff_t for composition IDs.

* character.c (lisp_string_width):
* composite.c (composition_table_size, n_compositions)
(get_composition_id, composition_gstring_from_id):
* dispextern.h (struct glyph_string.cmp_id, struct composition_it.id):
* xdisp.c (BUILD_COMPOSITE_GLYPH_STRING):
* window.c (Frecenter):
Use ptrdiff_t, not int, for composition IDs.
* composite.c (get_composition_id): Check for integer overflow.
* composite.h: Adjust prototypes to match the above changes.

1 files changed, 2 insertions, 2 deletions

diff --git a/src/dispextern.h b/src/dispextern.h
index bb4da7d52a8..1d7bf5d53ec 100644
--- a/src/dispextern.h
+++ b/src/dispextern.h
@@ -1240,7 +1240,7 @@ struct glyph_string
   struct composition *cmp;
 
   /* If not negative, this string describes a compos.  */
-  int cmp_id;
+  ptrdiff_t cmp_id;
 
   /* Start and end glyph indices in a glyph-string.  */
   int cmp_from, cmp_to;
@@ -2056,7 +2056,7 @@ struct composition_it
   EMACS_INT stop_pos;
   /* ID number of the composition or glyph-string.  If negative, we
      are not iterating over a composition now.  */
-  int id;
+  ptrdiff_t id;
   /* If non-negative, character that triggers the automatic
      composition at `stop_pos', and this is an automatic composition.
      If negative, this is a static composition.  This is set to -2