except.c:link_handler

[Andrew Haley <aph at redhat dot com>]

With some weird exception structures, link_handler() crashes with a
segfault.  It turns out that when link_handler() inserts an exception
range A above another range B, it does not fix up the 'outer' field of
siblings of B.  While this is a fairly simple thing to fix, I don't
believe it is a full solution to the problem, and there are still
circumstances which will break link_handler().  However, this patch
won't break anything and will fix some cases.  

This code needs to be revisited.

The class is org/eclipse/core/internal/resources/InternalWorkspaceJob.
This is the gloriously contorted exception map:

  start: 17, end: 68, handler: 68, type: org.eclipse.core.runtime.OperationCanceledException
  start: 17, end: 62, handler: 93, type: 0 /* finally */
  start: 68, end: 87, handler: 93, type: 0 /* finally */
  start: 5, end: 135, handler: 135, type: org.eclipse.core.runtime.CoreException
  start: 5, end: 65, handler: 148, type: 0 /* finally */
  start: 68, end: 90, handler: 148, type: 0 /* finally */
  start: 93, end: 145, handler: 148, type: 0 /* finally */

What we actually want to end up with:

0 - 167 -> outer (NULL)
  5 - 135 -> outer 0 - 167
    5 - 17 -> outer 5 - 135
    17 - 68 -> outer 5 - 135
      17 - 65 -> outer 17 - 68
        17 - 62 -> outer 17 - 65
    68 - 90 -> outer 5 - 135
      68 - 87 -> outer 68 - 90

Andrew.



2004-12-01  Andrew Haley  <aph@redhat.com>

	* except.c (link_handler): Patch 'outer' field of siblings of the
	range we're demoting.

Index: except.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/java/except.c,v
retrieving revision 1.46
diff -p -2 -c -r1.46 except.c
*** except.c	5 Aug 2004 05:52:00 -0000	1.46
--- except.c	1 Dec 2004 14:04:58 -0000
*************** link_handler (struct eh_range *range, st
*** 139,148 ****
        range->first_child = outer;
        {
  	struct eh_range **pr = &(outer->outer->first_child);
  	while (*pr != outer)
  	  pr = &(*pr)->next_sibling;
  	*pr = range;
        }
!       outer->outer = range;
        return;
      }
--- 139,155 ----
        range->first_child = outer;
        {
+ 	struct eh_range *p = outer;
  	struct eh_range **pr = &(outer->outer->first_child);
  	while (*pr != outer)
  	  pr = &(*pr)->next_sibling;
  	*pr = range;
+ 
+ 	while (p)
+ 	  {
+ 	    p->outer = range;
+ 	    p = p->next_sibling;
+ 	  }
        }
! 
        return;
      }