This is the mail archive of the cygwin-patches mailing list for the Cygwin project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: dlclose not calling destructors of static variables.


On 01/02/2010 19:28, Dave Korn wrote:
> On 01/02/2010 17:51, Christopher Faylor wrote:
>> On Mon, Feb 01, 2010 at 12:46:11PM -0500, Christopher Faylor wrote:
> 
>>>> Cribbing from the gdb source code, it looks like they use BaseAddrees + 
>>>> 0x1000 for the start point and then call GetModuleInformation to workout 
>>>> the size of the module.
>>> Yeah, duh.  "they" == "me".  I should have checked gdb for this since I've
>>> already done this research once before.
>>>
>>> If you do find that this works, then I think this may fall into the
>>> realm of a non-trivial patch so it may be best to just tell me what
>>> you've found rather than provide a patch - unless you want to go through
>>> the approval process with Red Hat.
>>>
>>> Or, you can just wait for me to adapt what's in gdb to cygwin.  I can do
>>> tonight when I get back to a windows system.
>> Btw, it isn't entirely clear that GetModuleInformation will work with
>> older versions of Windows NT so this may not be a complete solution.  We
>> do use GetModuleInformation in Cygwin but it is not in anything as
>> crucial as this.
> 
>   Can't we use the info in the dll struct?  It has pointers to the data and
> bss section, we could take the max out of them and the data in the M_B_I
> struct.  (Tell you what, I'll try it.)

  Yep, that makes the original testcase work for me.  How about it?

winsup/cygwin/ChangeLog:


	* dll_init.cc (remove_dll_atexit): Take pointer to dll and
	estimate end of dll more generously.
	(dll_list::detach): Update caller.

  (This is just the first patch on its way relating to this subject.)

    cheers,
      DaveK
Index: dll_init.cc
===================================================================
RCS file: /cvs/src/src/winsup/cygwin/dll_init.cc,v
retrieving revision 1.68
diff -p -u -r1.68 dll_init.cc
--- dll_init.cc	29 Jan 2010 18:34:09 -0000	1.68
+++ dll_init.cc	1 Feb 2010 19:55:10 -0000
@@ -153,11 +153,15 @@ dll_list::alloc (HINSTANCE h, per_proces
    register an atexit function outside of the DLL and that should be
    run when the DLL detachs.  */
 static void
-remove_dll_atexit (MEMORY_BASIC_INFORMATION& m)
+remove_dll_atexit (const MEMORY_BASIC_INFORMATION& m, const dll *d)
 {
   unsigned char *dll_beg = (unsigned char *) m.AllocationBase;
   unsigned char *dll_end = (unsigned char *) m.AllocationBase + m.RegionSize;
   struct _atexit *p = _GLOBAL_REENT->_atexit;
+  if (dll_end < d->p.data_end)
+    dll_end = (unsigned char *) d->p.data_end;
+  if (dll_end < d->p.bss_end)
+    dll_end = (unsigned char *) d->p.bss_end;
   for (int n = p->_ind - 1; n >= 0; n--)
     {
       void (*fn) (void) = p->_fns[n];
@@ -188,7 +192,7 @@ dll_list::detach (void *retaddr)
       system_printf ("WARNING: trying to detach an already detached dll ...");
     else if (--d->count == 0)
       {
-	remove_dll_atexit (m);
+	remove_dll_atexit (m, d);
 	d->run_dtors ();
 	d->prev->next = d->next;
 	if (d->next)

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]