(check_composition): Check validity of composition.

diff --git a/src/indent.c b/src/indent.c
index f10221b082a37caa8485e62f6d6ddfc54b629fb2..9e187b80d3f3f0f2c60068fe7eea8e8d8350f3a5 100644 (file)
--- a/src/indent.c
+++ b/src/indent.c
@@ -281,7 +281,8 @@ check_composition (pos, pos_byte, point, len, len_byte, width)
   int id;
 
   if (! find_composition (pos, -1, &start, &end, &prop, Qnil)
-      || pos != start || point < end)
+      || pos != start || point < end
+      || !COMPOSITION_VALID_P (start, end, prop))
     return 0;
   if ((id = get_composition_id (pos, pos_byte, end - pos, prop, Qnil)) < 0)
     return 0;