1 files changed, 3 insertions, 6 deletions

diff --git a/src/category.c b/src/category.c
index e6c180f29c1..4e89c98a027 100644
--- a/src/category.c
+++ b/src/category.c
@@ -364,18 +364,15 @@ then delete CATEGORY from the category set instead of adding it.  */)
   while (start <= end)
     {
       category_set = char_table_ref_and_range (table, start, &from, &to);
-      if (from < start || to > end)
-        category_set = Fcopy_sequence (category_set);
-      SET_CATEGORY_SET (category_set, category, set_value);
-      if (from < start)
+      if (CATEGORY_MEMBER (category, category_set) != NILP (reset))
         {
+          category_set = Fcopy_sequence (category_set);
+          SET_CATEGORY_SET (category_set, category, set_value);
           if (to > end)
             char_table_set_range (table, start, end, category_set);
           else
             char_table_set_range (table, start, to, category_set);
         }
-      else if (to > end)
-        char_table_set_range (table, start, end, category_set);
       start = to + 1;
     }
   return Qnil;