Although the fixes described in my previous e-mail, especially the
second one, correct the crashing problem, there is the problem
of seemingly redundant calls to _XmListDeselectPos() for the
same position, which are not handled correctly. Upon deselecting
all items prior to unmanaging the list - a process that works
correctly under OSF Motif - I get a warning for the last selected
position:
Warning:
Name: PreTransform Test List
Class: XmList
XmListDeselectPos(377) : item not found in selectedItems.
I haven't yet been able to determine the cause of this problem,
but backing out the first recommended fix (at line 2289) did not
correct it, so it's apparently an existing problem that was hidden
by the previous more serious memory error and thus never fixed.
----- Original Message -----
From: Jerry Miller <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Monday, July 23, 2001 11:25 AM
Subject: Bugs in _XmListDeselectPos() and _XmListInvokeCallbacks()
> I've found two bugs in List.c that are corrupting and/or crashing
> multiple-selection lists. The first is in _XmListDeselectPos(),
> line 2289 - a single loop statement that should be a block, both
> for correctness and for symmetry with _XmListSelectPos():
>
> List_SelectedIndices(w)[j] = List_SelectedIndices(w)[j + 1];
>
> should be:
>
> {
> List_SelectedIndices(w)[j] = List_SelectedIndices(w)[j
+
> 1];
> if (List_SelectedItems(w))
> List_SelectedItems(w)[j] = List_SelectedItems(w)[j + 1];
> }
>
> ------------------------------------------------------------------
>
> The second bug is in _XmListInvokeCallbacks(), where a copy of
> the selected items is made before calling the callbacks and is freed
> afterward on the basis of an updated count, which means that the
> copy may not be freed correctly - line 2348 should be preceded by:
>
> int saved_items_count;
>
> line 2431 should be preceded by:
>
> saved_items_count = List_SelectedItemCount(w);
>
> and line 2457 should be replaced with:
>
> for (i = 0; i < /* List_SelectedItemCount(w) */ saved_items_count;
> i++)
>
