(Fprevious_single_char_property_change): Don't do arithmetic directly on lisp

objects.

1 files changed, 4 insertions, 2 deletions

diff --git a/src/textprop.c b/src/textprop.c
index f96e6bb6e7d..a14480bf294 100644
--- a/src/textprop.c
+++ b/src/textprop.c
@@ -790,7 +790,8 @@ back past position LIMIT; return LIMIT if nothing is found before LIMIT.")
       else
         {
           Lisp_Object initial_value =
-            Fget_char_property (position - 1, prop, object);
+            Fget_char_property (make_number (XFASTINT (position) - 1),
+                                prop, object);
       
           for (;;)
             {
@@ -804,7 +805,8 @@ back past position LIMIT; return LIMIT if nothing is found before LIMIT.")
               else
                 {
                   Lisp_Object value =
-                    Fget_char_property (position - 1, prop, object);
+                    Fget_char_property (make_number (XFASTINT (position) - 1),
+                                        prop, object);
 
                   if (!EQ (value, initial_value))
                     break;