Check for overflow when converting integer to cons and back.

* charset.c (Fdefine_charset_internal, Fdecode_char):
Use cons_to_unsigned to catch overflow.
(Fencode_char): Use INTEGER_TO_CONS.
* composite.h (LGLYPH_CODE): Use cons_to_unsigned.
(LGLYPH_SET_CODE): Use INTEGER_TO_CONS.
* data.c (long_to_cons, cons_to_long): Remove.
(cons_to_unsigned, cons_to_signed): New functions.
These signal an error for invalid or out-of-range values.
* dired.c (Ffile_attributes): Use INTEGER_TO_CONS.
* fileio.c (Fset_visited_file_modtime): Use CONS_TO_INTEGER.
* font.c (Ffont_variation_glyphs):
* fontset.c (Finternal_char_font): Use INTEGER_TO_CONS.
* lisp.h: Include <intprops.h>.
(INTEGER_TO_CONS, CONS_TO_INTEGER): New macros.
(cons_to_signed, cons_to_unsigned): New decls.
(long_to_cons, cons_to_long): Remove decls.
* undo.c (record_first_change): Use INTEGER_TO_CONS.
(Fprimitive_undo): Use CONS_TO_INTEGER.
* xfns.c (Fx_window_property): Likewise.
* xselect.c: Include <limits.h>.
(x_own_selection, selection_data_to_lisp_data):
Use INTEGER_TO_CONS.
(x_handle_selection_request, x_handle_selection_clear)
(x_get_foreign_selection, Fx_disown_selection_internal)
(Fx_get_atom_name, x_send_client_event): Use CONS_TO_INTEGER.
(lisp_data_to_selection_data): Use cons_to_unsigned.
(x_fill_property_data): Use cons_to_signed.
Report values out of range.

1 files changed, 1 insertions, 7 deletions

diff --git a/src/fontset.c b/src/fontset.c
index 46637b53b3e..fec3c56b036 100644
--- a/src/fontset.c
+++ b/src/fontset.c
@@ -1859,17 +1859,11 @@ DEFUN ("internal-char-font", Finternal_char_font, Sinternal_char_font, 1, 2, 0,
     {
       unsigned code = face->font->driver->encode_char (face->font, c);
       Lisp_Object font_object;
-      /* Assignment to EMACS_INT stops GCC whining about limited range
-         of data type.  */
-      EMACS_INT cod = code;
 
       if (code == FONT_INVALID_CODE)
         return Qnil;
       XSETFONT (font_object, face->font);
-      if (cod <= MOST_POSITIVE_FIXNUM)
-        return Fcons (font_object, make_number (code));
-      return Fcons (font_object, Fcons (make_number (code >> 16),
-                                     make_number (code & 0xFFFF)));
+      return Fcons (font_object, INTEGER_TO_CONS (code));
     }
   return Qnil;
 }