[Bug c++/56742] New: Optimization bug lead to uncaught throw

[Bug c++/56742] New: Optimization bug lead to uncaught throw

[ktietz at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56742

             Bug #: 56742
           Summary: Optimization bug lead to uncaught throw
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: ktietz@gcc.gnu.org
            Target: x86_64-w64-mingw32, x86_64-pc-cygwin


Hi,

the following testcase:

#include <string>

static int main_worker(int argc)
{
  std::string s[32]; // [31] => no segfault
  if (argc < 2)
    throw 42;
  return argc;
}

int main(int argc, char **argv)
{
  try {
    return main_worker(argc);
  }
  catch (int i) {
    return i;
  }
}

produces with optimization -O2 on execution the message:
 "terminate called after throwing an instance of 'int'"
and abort gets called.

If compiled with optimization level -O1, execution works as expected.

[Bug c++/56742] Optimization bug lead to uncaught throw

[ktietz at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56742

Kai Tietz <ktietz at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |wrong-code
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2013-03-26
     Ever Confirmed|0                           |1
      Known to fail|                            |4.8.0

[Bug c++/56742] Optimization bug lead to uncaught throw

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56742

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |franke at computer dot org

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> 2013-03-26 20:11:28 UTC ---
*** Bug 56747 has been marked as a duplicate of this bug. ***

[Bug c++/56742] Optimization bug lead to uncaught throw

[ktietz at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56742

--- Comment #2 from Kai Tietz <ktietz at gcc dot gnu.org> 2013-03-26 21:14:23 UTC ---
Hmm, yes indeed it is the -freorder-blocks option. One solution is to disallow
after reload for SEH-target to modify jumps.

The following patch fixes the issue for me.


Index: i386.c
===================================================================
--- i386.c      (Revision 197118)
+++ i386.c      (Arbeitskopie)
@@ -3941,6 +3941,19 @@
   register_pass (&insert_vzeroupper_info);
 }

+/* Implement TARGET_CANNOT_MODIFY_JUMPS_P.  */
+static bool
+ix86_cannot_modify_jumps_p (void)
+{
+  if (TARGET_SEH && reload_completed
+      && cfun)
+    return true;
+  return false;
+}
+
+#undef  TARGET_CANNOT_MODIFY_JUMPS_P
+#define TARGET_CANNOT_MODIFY_JUMPS_P ix86_cannot_modify_jumps_p
+
 /* Update register usage after having seen the compiler flags.  */

 static void

[Bug c++/56742] Optimization bug lead to uncaught throw

[steven at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56742

Steven Bosscher <steven at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |steven at gcc dot gnu.org

--- Comment #3 from Steven Bosscher <steven at gcc dot gnu.org> 2013-03-26 23:43:40 UTC ---
(In reply to comment #2)
> Hmm, yes indeed it is the -freorder-blocks option. One solution is to 
> disallow after reload for SEH-target to modify jumps.

That's an awfully big hammer. Perhaps it's possible to first analyze
what is actually happening in bbreorder that causes this bug?

[Bug c++/56742] Optimization bug lead to uncaught throw

[ktietz at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56742

--- Comment #4 from Kai Tietz <ktietz at gcc dot gnu.org> 2013-03-27 09:40:16 UTC ---
(In reply to comment #3)
> (In reply to comment #2)
> > Hmm, yes indeed it is the -freorder-blocks option. One solution is to 
> > disallow after reload for SEH-target to modify jumps.
> 
> That's an awfully big hammer. Perhaps it's possible to first analyze
> what is actually happening in bbreorder that causes this bug?

Well, the issue is analyzed.  The issue is that SEH is table-based EH, and so
after bb-reorder used labels for describing eh-regions are getting invalid.
If you take a look to the produces assembly for the example, you will notice
that easily.
I admit that the first patch is a bit too invasive, as it disables bb-reorder
in all cases.  But in fact we need to disable it just if there is a
catch-region. A more improved variant is:

Index: i386.c
===================================================================
--- i386.c      (Revision 197118)
+++ i386.c      (Arbeitskopie)
@@ -3941,6 +3941,20 @@
   register_pass (&insert_vzeroupper_info);
 }

+/* Implement TARGET_CANNOT_MODIFY_JUMPS_P.  */
+static bool
+ix86_cannot_modify_jumps_p (void)
+{
+  if (TARGET_SEH && reload_completed
+      && cfun && cfun->eh
+      && cfun->eh->region_tree)
+    return true;
+  return false;
+}
+
+#undef  TARGET_CANNOT_MODIFY_JUMPS_P
+#define TARGET_CANNOT_MODIFY_JUMPS_P ix86_cannot_modify_jumps_p
+
 /* Update register usage after having seen the compiler flags.  */

 static void

[Bug rtl-optimization/56742] Optimization bug lead to uncaught throw

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56742

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jason at gcc dot gnu.org
          Component|c++                         |rtl-optimization

--- Comment #5 from Jason Merrill <jason at gcc dot gnu.org> 2013-03-27 13:48:42 UTC ---
I can't reproduce this on x86_64-unknown-linux-gnu.

Is it a regression?

Changing component to rtl-optimization.

[Bug rtl-optimization/56742] Optimization bug lead to uncaught throw

[ktietz at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56742

--- Comment #6 from Kai Tietz <ktietz at gcc dot gnu.org> 2013-03-27 14:43:24 UTC ---
Well, this issue is related to SEH exceptions.  So it is pretty clear, why you
don't see it for linux.

It is serious bug for 4.8 gcc.  From user's perspective this is a regression. 
Technical it is a bug in bb-reorder for SEH.
For 4.8 I think the above patch is the lowest invasive way to fix it.  For
trunk we might be able to use an approach as dw2 uses here.  Not sure about
later.  I will discuss with Richard Henderson.

[Bug rtl-optimization/56742] [4.8 regression] Optimization bug lead to uncaught throw

[ktietz at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56742

Kai Tietz <ktietz at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.8.1
            Summary|Optimization bug lead to    |[4.8 regression]
                   |uncaught throw              |Optimization bug lead to
                   |                            |uncaught throw

[Bug rtl-optimization/56742] [4.8 regression] Optimization bug lead to uncaught throw

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56742

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #7 from Jakub Jelinek <jakub at gcc dot gnu.org> 2013-04-26 18:16:54 UTC ---
Does it work with 4.9?  If not, it should be marked as 4.8/4.9 Regression.

[Bug rtl-optimization/56742] [4.8/4.9 regression] Optimization bug lead to uncaught throw

[rth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56742

Richard Henderson <rth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |rth at gcc dot gnu.org
   Target Milestone|4.8.1                       |4.8.2
            Summary|[4.8 regression]            |[4.8/4.9 regression]
                   |Optimization bug lead to    |Optimization bug lead to
                   |uncaught throw              |uncaught throw

[Bug rtl-optimization/56742] [4.8/4.9 regression] Optimization bug lead to uncaught throw

[rth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56742

Richard Henderson <rth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |rth at gcc dot gnu.org

--- Comment #8 from Richard Henderson <rth at gcc dot gnu.org> ---
Mine.

[Bug rtl-optimization/56742] [4.8/4.9 regression] Optimization bug lead to uncaught throw

[rth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56742

--- Comment #9 from Richard Henderson <rth at gcc dot gnu.org> ---
Created attachment 30168
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=30168&action=edit
proposed patch

Kudos to Kai for finally figuring out what was going wrong inside the
system unwinder, and why.

I believe this patch will fix the problem -- at least it does for this
test case.  A full test cycle is just commencing...

[Bug rtl-optimization/56742] [4.8/4.9 regression] Optimization bug lead to uncaught throw

[rth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56742

Richard Henderson <rth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #30168|0                           |1
        is obsolete|                            |

--- Comment #10 from Richard Henderson <rth at gcc dot gnu.org> ---
Created attachment 30169
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=30169&action=edit
proposed patch 2

Fixes a dwarf2 ICE caused by the previous version.
Full testing just restarting...

[Bug rtl-optimization/56742] [4.8/4.9 regression] Optimization bug lead to uncaught throw

[rth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56742

Richard Henderson <rth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED

--- Comment #11 from Richard Henderson <rth at gcc dot gnu.org> ---
Fixed.

[Bug rtl-optimization/56742] [4.8/4.9 regression] Optimization bug lead to uncaught throw

[g63marty at yahoo dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56742

at2010 <g63marty at yahoo dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |g63marty at yahoo dot com

--- Comment #12 from at2010 <g63marty at yahoo dot com> ---
Created attachment 31834
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=31834&action=edit
save output log and debug window log (at end)

[Bug rtl-optimization/56742] [4.8/4.9 regression] Optimization bug lead to uncaught throw

[g63marty at yahoo dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56742

--- Comment #13 from at2010 <g63marty at yahoo dot com> ---
Hello.

I also observed the 64bit compile problem while muxing. And after using the new
build the problem is indeed resolved. However I still see a remnant wxwiget
error in the logs that you may wish to fix as well.
Error is
In file
/home/mosu/prog/video/mingw/cross-git-all/tmp-wxwidgets/wxWidgets-3.0.0/src/msw/window.cpp
at line 576: 'SetFocus' failed with error 0x00000057 (the parameter is
incorrect.).

This is the pre-fix log. The post-fix log is below.

mkvmerge v6.7.0 ('Back to the Ground') 64bit built on Jan  8 2014 15:10:52

'notrealfilename.avi': Using the demultiplexer for the format 'AVI'.

'notrealfilename.avi' track 0: Using the output module for the format 'MPEG-4'.

'notrealfilename.avi' track 1: Using the output module for the format 'AC3'.

The file 'notrealfilename (1).mkv' has been opened for writing.

Progress: 0%

[Fails with return code 3]

Output of Debug window:
12:34:22: dpi is 96/96
12:34:22: Querying mkvmerge's capabilities
12:34:23: Capability: VERSION=mkvmerge v6.7.0 ('Back to the Ground') 64bit
built on Jan  8 2014 15:10:52
12:34:23: Capability: 
12:34:23: Capability: FLAC
12:34:23: Capability: 
12:34:23: about to check... btw int? 0
12:34:23: update state changed, now 1
12:34:26: update state changed, now 2
12:34:32: identify 1: command: ``"C:\Program Files
(x86)\MKVToolNix\mkvmerge.exe"
"@C:\Users\notme\AppData\Local\Temp\mmg-mkvmerge-options-3992-1389731672"''
12:34:33: identify 1: result: 0
12:34:33: identify 1: output[0]: ``File 'notrealfilename.avi': container: AVI
[is_providing_timecodes:1]''
12:34:33: identify 1: output[1]: ``''
12:34:33: identify 1: output[2]: ``Track ID 0: video (MPEG-4p2)''
12:34:33: identify 1: output[3]: ``''
12:34:33: identify 1: output[4]: ``Track ID 1: audio (AC3/EAC3)''
12:34:33: identify 1: output[5]: ``''
12:36:58: Locale selection logic: select_locale English (English)
uu_locale_lower en translation_c::get_default_ui_locale() en app->m_ui_locale
en
12:37:20: Querying mkvmerge's capabilities
12:37:20: Capability: VERSION=mkvmerge v6.7.0 ('Back to the Ground') 64bit
built on Jan  8 2014 15:10:52
12:37:20: Capability: 
12:37:20: Capability: FLAC
12:37:20: Capability: 
In file
/home/mosu/prog/video/mingw/cross-git-all/tmp-wxwidgets/wxWidgets-3.0.0/src/msw/window.cpp
at line 576: 'SetFocus' failed with error 0x00000057 (the parameter is
incorrect.).
In file
/home/mosu/prog/video/mingw/cross-git-all/tmp-wxwidgets/wxWidgets-3.0.0/src/msw/window.cpp
at line 576: 'SetFocus' failed with error 0x00000057 (the parameter is
incorrect.).
In file
/home/mosu/prog/video/mingw/cross-git-all/tmp-wxwidgets/wxWidgets-3.0.0/src/msw/window.cpp
at line 576: 'SetFocus' failed with error 0x00000057 (the parameter is
incorrect.).
In file
/home/mosu/prog/video/mingw/cross-git-all/tmp-wxwidgets/wxWidgets-3.0.0/src/msw/window.cpp
at line 576: 'SetFocus' failed with error 0x00000057 (the parameter is
incorrect.).

12:57:49: dpi is 96/96
12:57:49: Querying mkvmerge's capabilities
12:57:49: Capability: VERSION=mkvmerge v6.7.0 ('Back to the Ground') 64bit
built on Jan  8 2014 15:10:52
12:57:49: Capability: 
12:57:49: Capability: FLAC
12:57:49: Capability: 
12:58:00: identify 1: command: ``"C:\Program Files
(x86)\MKVToolNix\mkvmerge.exe"
"@C:\Users\Marty\AppData\Local\Temp\mmg-mkvmerge-options-4540-1389733080"''
12:58:01: identify 1: result: 0
12:58:01: identify 1: output[0]: ``File 'notrealfilename.avi': container: AVI
[is_providing_timecodes:1]''
12:58:01: identify 1: output[1]: ``''
12:58:01: identify 1: output[2]: ``Track ID 0: video (MPEG-4p2)''
12:58:01: identify 1: output[3]: ``''
12:58:01: identify 1: output[4]: ``Track ID 1: audio (AC3/EAC3)''
12:58:01: identify 1: output[5]: ``''
In file
/home/mosu/prog/video/mingw/cross-git-all/tmp-wxwidgets/wxWidgets-3.0.0/src/msw/window.cpp
at line 576: 'SetFocus' failed with error 0x00000057 (the parameter is
incorrect.).


mkvmerge v6.7.0 ('Back to the Ground') 64bit built on Jan 11 2014 10:17:39

'notrealfilename.avi': Using the demultiplexer for the format 'AVI'.

'notrealfilename.avi' track 0: Using the output module for the format 'MPEG-4'.

'notrealfilename.avi' track 1: Using the output module for the format 'AC3'.

The file 'notrealfilename (2).mkv' has been opened for writing.


Progress: 0%
[omitted lines]
Progress: 100%

The cue entries (the index) are being written...
Muxing took 53 seconds.


Output of Debug window:
13:01:17: dpi is 96/96
13:01:17: Querying mkvmerge's capabilities
13:01:17: Capability: VERSION=mkvmerge v6.7.0 ('Back to the Ground') 64bit
built on Jan 11 2014 10:17:39
13:01:17: Capability: 
13:01:17: Capability: FLAC
13:01:17: Capability: 
13:01:36: identify 1: command: ``"C:\Program Files
(x86)\MKVToolNix\mkvmerge.exe"
"@C:\Users\notme\AppData\Local\Temp\mmg-mkvmerge-options-4456-1389733296"''
13:01:37: identify 1: result: 0
13:01:37: identify 1: output[0]: ``File 'notrealfilename.avi': container: AVI
[is_providing_timecodes:1]''
13:01:37: identify 1: output[1]: ``Track ID 0: video (MPEG-4p2)''
13:01:37: identify 1: output[2]: ``Track ID 1: audio (AC3/EAC3)''
13:01:37: identify 1: output[3]: ``''
In file
/home/mosu/prog/video/mingw/cross-git-all/tmp-wxwidgets/wxWidgets-3.0.0/src/msw/window.cpp
at line 576: 'SetFocus' failed with error 0x00000057 (the parameter is
incorrect.).