[Bug tree-optimization/61536] New: [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[Bug tree-optimization/61536] New: [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[ramana at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61536

            Bug ID: 61536
           Summary: [4.10 regression] g++ and libstdc++ regressions on
                    arm-none-linux-gnueabihf with missing typeinfo
           Product: gcc
           Version: 4.10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ramana at gcc dot gnu.org

rev: 211358

https://gcc.gnu.org/ml/gcc-testresults/2014-06/msg00821.html


rev: 211354

https://gcc.gnu.org/ml/gcc-testresults/2014-06/msg00803.html


Test suite differences in g++ , libstdc++ with link time failures that look
like 


FAIL: g++.dg/opt/typeinfo1.C -std=gnu++1y (test for excess errors)
Excess errors:
typeinfo1.C:(.text+0x18): undefined reference to
`std::type_info::operator==(std::type_info const&) const'
typeinfo1.C:(.text.startup+0x20): undefined reference to
`std::type_info::operator==(std::type_info const&) const'
typeinfo1.C:(.text.startup+0x44): undefined reference to
`std::type_info::operator==(std::type_info const&) const'

[Bug tree-optimization/61536] [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[ramana at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61536

Ramana Radhakrishnan <ramana at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |link-failure
             Target|                            |arm-none-linux-gnueabihf
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2014-06-17
      Known to work|                            |4.8.0, 4.8.1, 4.8.2, 4.8.3,
                   |                            |4.9.0
   Target Milestone|---                         |4.10.0
     Ever confirmed|0                           |1

[Bug tree-optimization/61536] [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[ramana at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61536

Ramana Radhakrishnan <ramana at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |hubicka at gcc dot gnu.org,
                   |                            |paolo at gcc dot gnu.org

--- Comment #1 from Ramana Radhakrishnan <ramana at gcc dot gnu.org> ---
Linkage for this passes if --static is given on the command line which
indicates this must be related to r211355-211357.

[Bug libstdc++/61536] [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[paolo.carlini at oracle dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61536

Paolo Carlini <paolo.carlini at oracle dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
                 CC|paolo at gcc dot gnu.org           |
          Component|tree-optimization           |libstdc++
           Assignee|unassigned at gcc dot gnu.org      |paolo.carlini at oracle dot com

--- Comment #2 from Paolo Carlini <paolo.carlini at oracle dot com> ---
Pretty sure it's my change because typeinfo::before and typeinfo::operator==
are special on some targets and I couldn't notice on x86-linux:

#if !__GXX_TYPEINFO_EQUALITY_INLINE
    // In old abi, or when weak symbols are not supported, there can
    // be multiple instances of a type_info object for one
    // type. Uniqueness must use the _name value, not object address.
    bool before(const type_info& __arg) const _GLIBCXX_NOEXCEPT;
    bool operator==(const type_info& __arg) const _GLIBCXX_NOEXCEPT;

however, I can get to this only next week, I'm traveling now, thus, if you
like, feel free to revert for now my commit and close this bug.

[Bug libstdc++/61536] [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[paolo.carlini at oracle dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61536

--- Comment #3 from Paolo Carlini <paolo.carlini at oracle dot com> ---
By the way, it would be useful if you could confirm the analysis, thus run nm
on your runtime .so and double check that those two symbols are there, but t,
instead of T.

[Bug libstdc++/61536] [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[ramana at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61536

--- Comment #4 from Ramana Radhakrishnan <ramana at gcc dot gnu.org> ---
(In reply to Paolo Carlini from comment #3)
> By the way, it would be useful if you could confirm the analysis, thus run
> nm on your runtime .so and double check that those two symbols are there,
> but t, instead of T.

It certainly looks like your change broke it and I was trying to tighten the
symbol regexps rather than reverting your changes completely but didn't fully
succeed yet.

(In reply to Paolo Carlini from comment #3)
> By the way, it would be useful if you could confirm the analysis, thus run
> nm on your runtime .so and double check that those two symbols are there,
> but t, instead of T.

An nm comparison showed the difference of one symbol on libstdc++.so

_ZNKSt9type_info6beforeERKS_

Sounds pretty much like that's the issue.

If you're ok, I'm happy to currently just revert your change and we can deal
with this later ?

[Bug libstdc++/61536] [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[paolo.carlini at oracle dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61536

--- Comment #5 from Paolo Carlini <paolo.carlini at oracle dot com> ---
Thanks. Before reverting the whole thing, please see if something like the
patchlet I'm going to attach works for you. It should.

[Bug libstdc++/61536] [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[paolo.carlini at oracle dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61536

--- Comment #6 from Paolo Carlini <paolo.carlini at oracle dot com> ---
Created attachment 32955
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=32955&action=edit
Draft

[Bug libstdc++/61536] [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[ramana at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61536

--- Comment #7 from Ramana Radhakrishnan <ramana at gcc dot gnu.org> ---
(In reply to Paolo Carlini from comment #6)
> Created attachment 32955 [details]
> Draft

I see other failures that include operator std::type_info::operator!= , so I'll
see how to extend this if it fixes the basic issues.


ZNKSt9type_infone* (In reply to Paolo Carlini from comment #6)
> Created attachment 32955 [details]
> Draft

[Bug libstdc++/61536] [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[paolo.carlini at oracle dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61536

Paolo Carlini <paolo.carlini at oracle dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |NEW
                 CC|hubicka at gcc dot gnu.org         |

--- Comment #8 from Paolo Carlini <paolo.carlini at oracle dot com> ---
Uhmm, we aren't actually checking the arm-linux ABI in libstc++/config, thus if
you are missing operator!=, which is inline for all targets (and not exported
for all the targets for which we check the ABI), I'm afraid all the bets are
off: before my changes you may have relied on *any* inline symbol, elsewhere
too. I would then recommend reverting for now my changes and closing this bug.
Thanks.

[Bug libstdc++/61536] [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[ramana at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61536

--- Comment #10 from Ramana Radhakrishnan <ramana at gcc dot gnu.org> ---
(In reply to Paolo Carlini from comment #9)
> Well, up to you really: maybe operator!= is special for you because it just
> thinly wraps operator== which is exported for you. If adding back *only*
> that additional export under the macro works, all your tests are fine, it
> would be great. Otherwise, just revert. Sorry again for the breakage.

I'll play with it and see what else comes out of it. 


thanks for the prompt response and the help here.


Ramana

[Bug libstdc++/61536] [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[ramana at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61536

--- Comment #11 from Ramana Radhakrishnan <ramana at gcc dot gnu.org> ---
(In reply to Paolo Carlini from comment #2)
> Pretty sure it's my change because typeinfo::before and typeinfo::operator==
> are special on some targets and I couldn't notice on x86-linux:
> 
> #if !__GXX_TYPEINFO_EQUALITY_INLINE
>     // In old abi, or when weak symbols are not supported, there can
>     // be multiple instances of a type_info object for one
>     // type. Uniqueness must use the _name value, not object address.
>     bool before(const type_info& __arg) const _GLIBCXX_NOEXCEPT;
>     bool operator==(const type_info& __arg) const _GLIBCXX_NOEXCEPT;

Doh ! And the comment above that actually refers to ARM EABI systems which
includes Linux. 

> 
> however, I can get to this only next week, I'm traveling now, thus, if you
> like, feel free to revert for now my commit and close this bug.

[Bug libstdc++/61536] [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[ramana at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61536

--- Comment #12 from Ramana Radhakrishnan <ramana at gcc dot gnu.org> ---
(In reply to Paolo Carlini from comment #9)
> Well, up to you really: maybe operator!= is special for you because it just
> thinly wraps operator== which is exported for you. If adding back *only*
> that additional export under the macro works, all your tests are fine, it
> would be great. Otherwise, just revert. Sorry again for the breakage.

Hmm, looks like the patchlet might be enough to do the trick. It looks like I
misread the logs. Apologies, the link time failure was actually with == in 

In function `std::type_info::operator!=(std::type_info const&) const':
/work/gcc/libstdc++-v3/testsuite/18_support/type_info/hash_code.cc:51:
undefined reference to `std::type_info::operator==(std::type_info const&)
const'


Looks like it fixes my issue on ARM.

regards
Ramana

[Bug libstdc++/61536] [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[paolo.carlini at oracle dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61536

--- Comment #13 from Paolo Carlini <paolo.carlini at oracle dot com> ---
Excellent, that version is very safe. Are you willing to commit it? Otherwise,
I don't know when I can do it, maybe only Sunday. If you do that, you may want
to also add, after the first comment:

// By default follow the old inline rules to avoid ABI changes.

something like:

// (logic copied from libsupc++/typeinfo (libstdc++/61536)).

otherwise the patch is ready to go in.

[Bug libstdc++/61536] [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[ramana at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61536

--- Comment #14 from Ramana Radhakrishnan <ramana at gcc dot gnu.org> ---
Author: ramana
Date: Wed Jun 18 09:44:15 2014
New Revision: 211774

URL: https://gcc.gnu.org/viewcvs?rev=211774&root=gcc&view=rev
Log:
Fix libstdc++/61536 - Export out of line typeinfo comparison operators

2014-06-18  Paolo Carlini  <paolo.carlini@oracle.com>
        Ramana Radhakrishnan  <ramana.radhakrishnan@arm.com>

    PR libstdc++/61536
    * config/abi/pre/gnu.ver: Adjust for out of line comparisons.

Modified:
    trunk/libstdc++-v3/ChangeLog
    trunk/libstdc++-v3/config/abi/pre/gnu.ver

[Bug libstdc++/61536] [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[glisse at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61536

--- Comment #16 from Marc Glisse <glisse at gcc dot gnu.org> ---
I am now getting an abi_check failure on x86_64-linux-gnu on a -O0 -g build
because of this symbol. Is it expected?

1 incompatible symbols 
0
_ZNKSt9type_infoeqERKS_
std::type_info::operator==(std::type_info const&) const
version status: incompatible
GLIBCXX_3.4
type: function
status: added

[Bug libstdc++/61536] [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[paolo.carlini at oracle dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61536

--- Comment #17 from Paolo Carlini <paolo.carlini at oracle dot com> ---
It is not expected of course, but I'm traveling, I cannot look into it now, I
have no idea why is the symbol exported, is the macro we added for ARM
misbehaving somehow for Linux? I can't imagine how since the operator is
defined inline on targeta like Linux and the macro should be false.

[Bug libstdc++/61536] [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[paolo.carlini at oracle dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61536

--- Comment #18 from Paolo Carlini <paolo.carlini at oracle dot com> ---
In other terms, I don't see how !__GXX_TYPEINFO_EQUALITY_INLINE may end up
being true on x86_64-linux given the beginning of abi/pre/gnu.ver

[Bug libstdc++/61536] [4.10 regression] g++ and libstdc++ regressions on arm-none-linux-gnueabihf with missing typeinfo

[paolo at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61536

--- Comment #20 from paolo at gcc dot gnu.org <paolo at gcc dot gnu.org> ---
Author: paolo
Date: Sat Jun 28 15:53:30 2014
New Revision: 212104

URL: https://gcc.gnu.org/viewcvs?rev=212104&root=gcc&view=rev
Log:
2014-06-28  Paolo Carlini  <paolo.carlini@oracle.com>

    Revert:
    2014-06-18  Paolo Carlini  <paolo.carlini@oracle.com>
                Ramana Radhakrishnan  <ramana.radhakrishnan@arm.com>

    PR libstdc++/61536
    * config/abi/pre/gnu.ver: Adjust for out of line comparisons.

    2014-06-08  Paolo Carlini  <paolo.carlini@oracle.com>

    * config/abi/pre/gnu.ver: Tighten some patterns; tidy.

Modified:
    trunk/libstdc++-v3/ChangeLog
    trunk/libstdc++-v3/config/abi/pre/gnu.ver