[Bug lto/48042] New: lto segfaults while building Qt 4.7.2 with -g -flto -fwhole-program

[Bug lto/48042] New: lto segfaults while building Qt 4.7.2 with -g -flto -fwhole-program

[bero at arklinux dot org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48042

           Summary: lto segfaults while building Qt 4.7.2 with -g -flto
                    -fwhole-program
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: lto
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: bero@arklinux.org


Trying to build Qt 4.7.2 with -g -flto for the library and -g -flto
-fwhole-program for the tools crashes gcc.

[bero@matterhorn uic3]$ g++ -Wl,-rpath-link,/usr/src/ark/BUILD/qt/lib -m64 -O2
-g -Wl,-rpath,/usr/lib64/qt4-embedded/lib
-Wl,-rpath,/usr/lib64/qt4-embedded/lib -flto -fwhole-program -o
../../../bin/uic3 .obj/release-static-emb-x86_64/customwidgetsinfo.o
.obj/release-static-emb-x86_64/databaseinfo.o
.obj/release-static-emb-x86_64/driver.o
.obj/release-static-emb-x86_64/treewalker.o
.obj/release-static-emb-x86_64/ui4.o .obj/release-static-emb-x86_64/validator.o
.obj/release-static-emb-x86_64/cppextractimages.o
.obj/release-static-emb-x86_64/cppwritedeclaration.o
.obj/release-static-emb-x86_64/cppwriteicondata.o
.obj/release-static-emb-x86_64/cppwriteicondeclaration.o
.obj/release-static-emb-x86_64/cppwriteiconinitialization.o
.obj/release-static-emb-x86_64/cppwriteincludes.o
.obj/release-static-emb-x86_64/cppwriteinitialization.o
.obj/release-static-emb-x86_64/main.o
.obj/release-static-emb-x86_64/ui3reader.o
.obj/release-static-emb-x86_64/parser.o
.obj/release-static-emb-x86_64/domtool.o
.obj/release-static-emb-x86_64/object.o
.obj/release-static-emb-x86_64/subclassing.o
.obj/release-static-emb-x86_64/form.o
.obj/release-static-emb-x86_64/converter.o
.obj/release-static-emb-x86_64/widgetinfo.o
.obj/release-static-emb-x86_64/embed.o .obj/release-static-emb-x86_64/qt3to4.o
.obj/release-static-emb-x86_64/deps.o .obj/release-static-emb-x86_64/uic.o   
-L/usr/src/ark/BUILD/qt/lib -lQt3Support -L/usr/src/ark/BUILD/qt/lib -lQtSql
-lsqlite3 -lQtXml -lQtGui -ljpeg -lmng -ltiff -lpng -lfreetype -lQtNetwork
-lssl -lcrypto -lQtCore -lz -lm -ldl -pthread -lgthread-2.0 -lrt -lglib-2.0
-lpthread
lto1: internal compiler error: Segmentation fault
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.
lto-wrapper: g++ returned 1 exit status
/usr/bin/ld: lto-wrapper failed
collect2: ld returned 1 exit status

This is with yesterday's gcc svn (rev. 170774).

It works (and actually produces a working binary) if I omit -g. Replacing -g
with -ggdb or -gdrawf-4 doesn't change anything.

[Bug lto/48042] lto segfaults while building Qt 4.7.2 with -g -flto -fwhole-program

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48042

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |WAITING
   Last reconfirmed|                            |2011.03.09 11:37:32
     Ever Confirmed|0                           |1

--- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-09 11:37:32 UTC ---
Any chance you can reduce this to a managable testcase?  LTO and debug
information are not exactly best friends, but we at least try to avoid ICEs
like this.

[Bug lto/48042] lto segfaults while building Qt 4.7.2 with -g -flto -fwhole-program

[bero at arklinux dot org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48042

--- Comment #2 from bero at arklinux dot org 2011-03-09 12:58:58 UTC ---
Somewhat reduced, still too large:
$ g++ -m64 -O2 -g -flto  -o ../../../bin/uic3
.obj/release-static-emb-x86_64/widgetinfo.o -L/usr/src/ark/BUILD/qt/lib
-lQt3Support
lto1: internal compiler error: Segmentation fault
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.
lto-wrapper: g++ returned 1 exit status
/usr/bin/ld: lto-wrapper failed
collect2: ld returned 1 exit status

[Bug lto/48042] lto segfaults while building Qt 4.7.2 with -g -flto -fwhole-program

[bero at arklinux dot org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48042

--- Comment #3 from bero at arklinux dot org 2011-03-09 13:19:53 UTC ---
If I reduce widgetinfo.cpp to just say

#include <q3glist.h>

it still breaks and produces a different, potentially more useful error:


In file included from tools/q3glist.h:164:0,
                 from :88:
tools/q3gvector.cpp: In member function ‘write’:
tools/q3gvector.cpp:159:1: internal compiler error: Segmentation fault
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.
lto-wrapper: g++ returned 1 exit status
/usr/bin/ld: lto-wrapper failed
collect2: ld returned 1 exit status

[Bug lto/48042] lto segfaults while building Qt 4.7.2 with -g -flto -fwhole-program

[bero at arklinux dot org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48042

--- Comment #4 from bero at arklinux dot org 2011-03-09 13:27:24 UTC ---
Created attachment 23598
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=23598
Preprocessed source of remaining widgetinfo.cpp

Preprocessed source of remaining widgetinfo.cpp

$ g++ -g -O2 -flto -o test.o -c widgetinfo.i
$ g++ -g -O2 -flto -o test test.o -L/usr/src/ark/BUILD/qt/lib -lQt3Support
In file included from tools/q3glist.h:164:0,
                 from :88:
tools/q3gvector.cpp: In member function ‘write’:
tools/q3gvector.cpp:159:1: internal compiler error: Segmentation fault
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.
lto-wrapper: g++ returned 1 exit status
/usr/bin/ld: lto-wrapper failed
collect2: ld returned 1 exit status

Still requires a libQt3Support.so built with -flto to trigger the crash
though...

[Bug lto/48042] lto segfaults while building Qt 4.7.2 with -g -flto -fwhole-program

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48042

--- Comment #5 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-09 13:31:13 UTC ---
Would be interesting to know if it also happens without -fwhole-program
(I am assuming you either use the gold or GNU ld linker-plugin).

You can also try linking to the libQT object files instead of the .so
and reduce the set of required files by incremental linking
(-r -nostdlib).

[Bug lto/48042] lto segfaults while building Qt 4.7.2 with -g -flto -fwhole-program

[bero at arklinux dot org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48042

--- Comment #6 from bero at arklinux dot org 2011-03-09 15:02:55 UTC ---
Created attachment 23601
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=23601
stripped down libQt3Support.a

Here's a stripped down version of libQt3Support.a -- linking the preprocessed
widgetinfo.cpp to it causes the crash.

I have both ld 2.21.51.0.6.20110118 with plugin support and gold 1.10
installed; not sure which gcc uses by default. /usr/bin/ld is ld.

[Bug lto/48042] lto segfaults while building Qt 4.7.2 with -g -flto -fwhole-program

[bero at arklinux dot org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48042

bero at arklinux dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #23598|0                           |1
        is obsolete|                            |
  Attachment #23601|0                           |1
        is obsolete|                            |

--- Comment #7 from bero at arklinux dot org 2011-03-09 16:27:45 UTC ---
Created attachment 23605
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=23605
Much smaller test case

Small self-contained test case, source-only.

$ tar xzf bug48042.tar.gz
$ cd bug48042
$ ./bug48042.sh
In file included from
../../../include/QtCore/../../src/corelib/global/qglobal.h:899:0,
                 from :10:
../../../include/Qt3Support/../../src/qt3support/tools/q3glist.h: In member
function ‘count’:
../../../include/Qt3Support/../../src/qt3support/tools/q3glist.h:161:1:
internal compiler error: Segmentation fault
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.
lto-wrapper: g++ returned 1 exit status
/usr/bin/ld: lto-wrapper failed
collect2: ld returned 1 exit status


The problem goes away if -g is added to the first compiler invocation as well
-- lto seems to fall over some constructs if linking is done with -g but an
object file was built without -g.

[Bug lto/48042] lto segfaults while building Qt 4.7.2 with -g -flto -fwhole-program

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48042

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |NEW

--- Comment #8 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-09 16:32:51 UTC ---
(In reply to comment #7)
> Created attachment 23605 [details]
> Much smaller test case
> 
> Small self-contained test case, source-only.
> 
> $ tar xzf bug48042.tar.gz
> $ cd bug48042
> $ ./bug48042.sh
> In file included from
> ../../../include/QtCore/../../src/corelib/global/qglobal.h:899:0,
>                  from :10:
> ../../../include/Qt3Support/../../src/qt3support/tools/q3glist.h: In member
> function ‘count’:
> ../../../include/Qt3Support/../../src/qt3support/tools/q3glist.h:161:1:
> internal compiler error: Segmentation fault
> Please submit a full bug report,
> with preprocessed source if appropriate.
> See <http://gcc.gnu.org/bugs.html> for instructions.
> lto-wrapper: g++ returned 1 exit status
> /usr/bin/ld: lto-wrapper failed
> collect2: ld returned 1 exit status
> 
> 
> The problem goes away if -g is added to the first compiler invocation as well
> -- lto seems to fall over some constructs if linking is done with -g but an
> object file was built without -g.

Ah, yeah - that's a known problem (and hard to fix).  What should work
is dropping -g at link time.

Basically to make your way reliably all conditional clearing in
free_lang_data_in_* based on debug_info_level checks have to be dropped.

[Bug lto/48042] lto segfaults while building Qt 4.7.2 with -g -flto -fwhole-program

[bero at arklinux dot org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48042

bero at arklinux dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #23605|0                           |1
        is obsolete|                            |

--- Comment #9 from bero at arklinux dot org 2011-03-09 16:46:24 UTC ---
Created attachment 23607
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=23607
Reduced test case

Reduced test case, comes down to 10 lines of code

[Bug lto/48042] lto segfaults while building Qt 4.7.2 with -g -flto -fwhole-program

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48042

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |lto

--- Comment #10 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-09 16:56:31 UTC ---
Thanks.  Quoted:

class A {
        virtual int x() = 0;
};

class B:public A {
        int x();
};

int B::x() {
}

rguenther@murzim:/tmp/bug48042> /space/rguenther/install/gcc-4.6.0/bin/g++ -c
test.cpp -flto
rguenther@murzim:/tmp/bug48042> /space/rguenther/install/gcc-4.6.0/bin/g++
test.o -flto -g
In file included from test.cpp:10:0,
                 from :5:
test.cpp: In member function 'x':
test.cpp:10:1: internal compiler error: Segmentation fault
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.

[Bug lto/48042] lto segfaults while building Qt 4.7.2 with -g -flto -fwhole-program

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48042

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |d.g.gorbachev at gmail dot
                   |                            |com

--- Comment #11 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-22 10:17:08 UTC ---
*** Bug 48225 has been marked as a duplicate of this bug. ***

[Bug lto/48042] lto segfaults while building Qt 4.7.2 with -g -flto -fwhole-program

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48042

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
         AssignedTo|unassigned at gcc dot       |rguenth at gcc dot gnu.org
                   |gnu.org                     |

--- Comment #12 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-12-09 12:08:06 UTC ---
I have a patch.

[Bug lto/48042] lto segfaults while building Qt 4.7.2 with -g -flto -fwhole-program

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48042

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.7.0

--- Comment #14 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-12-09 13:49:48 UTC ---
Fixed.

[Bug lto/48042] lto segfaults while building Qt 4.7.2 with -g -flto -fwhole-program

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48042

--- Comment #13 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-12-09 13:49:28 UTC ---
Author: rguenth
Date: Fri Dec  9 13:49:22 2011
New Revision: 182163

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=182163
Log:
2011-12-09  Richard Guenther  <rguenther@suse.de>

    PR lto/48042
    * tree.c (free_lang_data_in_decl): Remove freeing conditional
    on debuginfo level.

    * g++.dg/lto/pr48042_0.C: New testcase.

Added:
    trunk/gcc/testsuite/g++.dg/lto/pr48042_0.C
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree.c