Re: Strange problem with latest CVS

[Masatake YAMATO]

>     +           make_empty = 1;
>     +           tem      = startpos;
>     +           startpos = endpos;
>     +           endpos   = tem;
> 
> It is a bit convoluted, and I suspect it could be done more simply.
> However, if it fixes the bug, please install it.
> 
>     The biggest question is that whether I should use overlay-start or 
>     overlay-end to make an overlay empty.
> 
> It may not make much difference, but I think it is better to use
> overlay-end.  That is the earlier address in this case, and the result
> will be that the overlay stays before the inserted text.  However, I
> wouldn't say that the other choice is wrong.  In this bizarre
> situation, the best we can hope for is to keep things consistent, one
> way or another.

I have made the patch simpler. I will install this one.
Should I install it to HEAD?

2004-04-11  Masatake YAMATO  <address@hidden>

        * buffer.c (fix_start_end_in_overlays): make overlays 
        empty if they are backwards.

cvs diff: warning: unrecognized response `access control disabled, clients can 
connect from any host' from cvs server
Index: src/buffer.c
===================================================================
RCS file: /cvsroot/emacs/emacs/src/buffer.c,v
retrieving revision 1.446
diff -u -r1.446 buffer.c
--- src/buffer.c        25 Mar 2004 18:05:29 -0000      1.446
+++ src/buffer.c        10 Apr 2004 17:36:02 -0000
@@ -3290,8 +3290,7 @@
    endpoint in this range will need to be unlinked from the overlay
    list and reinserted in its proper place.
    Such an overlay might even have negative size at this point.
-   If so, we'll reverse the endpoints.  Can you think of anything
-   better to do in this situation?  */
+   If so, we'll make the overlay empty. */
 void
 fix_start_end_in_overlays (start, end)
      register int start, end;
@@ -3318,23 +3317,24 @@
   for (parent = NULL, tail = current_buffer->overlays_before; tail;)
     {
       XSETMISC (overlay, tail);
+
       endpos = OVERLAY_POSITION (OVERLAY_END (overlay));
+      startpos = OVERLAY_POSITION (OVERLAY_START (overlay));
+
+      /* If the overlay is backwards, make it empty.  */
+      if (endpos < startpos)
+       {
+         startpos = endpos;
+         Fset_marker (OVERLAY_START (overlay), make_number (startpos),
+                      Qnil);
+       }
+
       if (endpos < start)
        break;
-      startpos = OVERLAY_POSITION (OVERLAY_START (overlay));
+      
       if (endpos < end
          || (startpos >= start && startpos < end))
        {
-         /* If the overlay is backwards, fix that now.  */
-         if (startpos > endpos)
-           {
-             int tem;
-             Fset_marker (OVERLAY_START (overlay), make_number (endpos),
-                          Qnil);
-             Fset_marker (OVERLAY_END (overlay), make_number (startpos),
-                          Qnil);
-             tem = startpos; startpos = endpos; endpos = tem;
-           }
          /* Add it to the end of the wrong list.  Later on,
             recenter_overlay_lists will move it to the right place.  */
          if (endpos < current_buffer->overlay_center)
@@ -3365,22 +3365,24 @@
   for (parent = NULL, tail = current_buffer->overlays_after; tail;)
     {
       XSETMISC (overlay, tail);
+
       startpos = OVERLAY_POSITION (OVERLAY_START (overlay));
+      endpos = OVERLAY_POSITION (OVERLAY_END (overlay));
+
+      /* If the overlay is backwards, make it empty.  */
+      if (endpos < startpos)
+       {
+         startpos = endpos;
+         Fset_marker (OVERLAY_START (overlay), make_number (startpos),
+                      Qnil);     
+       }
+
       if (startpos >= end)
        break;
-      endpos = OVERLAY_POSITION (OVERLAY_END (overlay));
+
       if (startpos >= start
          || (endpos >= start && endpos < end))
        {
-         if (startpos > endpos)
-           {
-             int tem;
-             Fset_marker (OVERLAY_START (overlay), make_number (endpos),
-                          Qnil);
-             Fset_marker (OVERLAY_END (overlay), make_number (startpos),
-                          Qnil);
-             tem = startpos; startpos = endpos; endpos = tem;
-           }
          if (endpos < current_buffer->overlay_center)
            {
              if (!afterp)