--- a/src/insdel.c	Mon Aug 13 10:05:01 2007 +0200
+++ b/src/insdel.c	Mon Aug 13 10:05:51 2007 +0200
@@ -208,6 +208,7 @@
 #include "insdel.h"
 #include "lstream.h"
 #include "redisplay.h"
+#include "line-number.h"
 
 /* We write things this way because it's very important the
    MAX_BYTIND_GAP_SIZE_3 is a multiple of 3. (As it happens,
@@ -2438,6 +2439,8 @@
 	make_gap (buf, length - BUF_GAP_SIZE (buf));
     }
 
+  insert_invalidate_line_number_cache (buf, pos, nonreloc + offset, length);
+
   record_insert (buf, pos, cclen);
   BUF_MODIFF (buf)++;
   MARK_BUFFERS_CHANGED;
@@ -2625,6 +2628,8 @@
   bi_to = bufpos_to_bytind (buf, to);
   bc_numdel = bi_to - bi_from;
 
+  delete_invalidate_line_number_cache (buf, from, to);
+
   if (to == BUF_Z (buf) &&
       bi_from > BI_BUF_GPT (buf))
     {