[Bug libstdc++/103407] New: [12 regression] abi_check FAILs on Solaris

[Bug libstdc++/103407] New: [12 regression] abi_check FAILs on Solaris

[ro at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103407

            Bug ID: 103407
           Summary: [12 regression] abi_check FAILs on Solaris
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ro at gcc dot gnu.org
  Target Milestone: ---
            Target: *-*-solaris2.11

Between 20211111 (dc002e31fb2d001703278263ea3d1cef366018ae) and 20211113
(a246d7230b8f8b059b21a073e8a91c213dee9cf4),
abi_check began to FAIL on Solaris, both sparc and x86, 32 and 64-bit:

+FAIL: libstdc++-abi/abi_check

3 incompatible symbols
0
_ZSt10from_charsPKcS0_RfSt12chars_format
std::from_chars(char const*, char const*, float&, std::chars_format)
version status: incompatible
GLIBCXX_3.4.29
type: function
status: added


1
_ZSt10from_charsPKcS0_ReSt12chars_format
std::from_chars(char const*, char const*, long double&, std::chars_format)
version status: incompatible
GLIBCXX_3.4.29
type: function
status: added


2
_ZSt10from_charsPKcS0_RdSt12chars_format
std::from_chars(char const*, char const*, double&, std::chars_format)
version status: incompatible
GLIBCXX_3.4.29
type: function
status: added

This coincides with the introduction of the GLIBCXX_3.4.30 version.

After some searching, I found/remembered that the GCC 11.1 baselines on
Solaris explicitly had omitted those symbols:

https://gcc.gnu.org/pipermail/gcc-patches/2021-March/566167.html

to avoid having separate baselines for Solaris 11.3 (which lacks XPG7 support
and thus uselocale) and 11.4 (which is XPG7 conformant).

I'm uncertain how to handle this:

* bite the bullet and introduce separate baselines for both versions (still
  supported by GCC 12)

* filter out those symbols when generating baseline_symbols.txt

* something else

[Bug libstdc++/103407] [12 regression] abi_check FAILs on Solaris

[ro at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103407

Rainer Orth <ro at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |12.0

[Bug libstdc++/103407] [12 regression] abi_check FAILs on Solaris

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103407

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P1
           Keywords|                            |ABI

[Bug libstdc++/103407] [12 regression] abi_check FAILs on Solaris

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103407

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Rainer Orth from comment #0)
> * something else

This one! :-)

Patrick is in the process of replacing my janky std::from_chars implementation
with something faster and more standards-conforming, which will mean we stop
using strtof and strtod, and so don't need the uselocale kluge to make the
conversions locale-independent.

That should mean that the float and double overloads can be defined
unconditionally for Solaris 11.3.

Then we have two problems: If we add those symbols now, they would be in the
3.4.30 version for Solaris 11.3 and 3.4.29 for Solaris 11.4, which I assume you
don't want. Secondly, it wouldn't change anything for the long double overload.

[Bug libstdc++/103407] [12 regression] abi_check FAILs on Solaris

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103407

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2021-11-25
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
.

[Bug libstdc++/103407] [12 regression] abi_check FAILs on Solaris

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103407

--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> ---
The new std::from_chars is on trunk, but we still have this in <charconv>:

#if _GLIBCXX_HAVE_USELOCALE

Which should be relaxed to not depend on uselocale.

[Bug libstdc++/103407] [12 regression] abi_check FAILs on Solaris

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103407

--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Rainer, is an executable linked against libstdc++.so.6.0.29 on Solaris 11.3
expected to work on an 11.4 machine with libstdc++.so.6.0.30?

With a #ifdef kluge in config/abi/pre/gnu.ver we can make the new from_chars
symbols get version GLIBCXX_3.4.30 on 11.3 and keep them at version 3.4.29 for
11.4. But that would mean a program linked on 11.3 and looking for
_ZSt10from_charsPKcS0_RdSt12chars_format@GLIBCXX_3.4.30 would not find it on
11.4. We can fix that with some symbol aliases for Solaris 11.4 to make it
available for both symbol versions if needed.

[Bug libstdc++/103407] [12 regression] abi_check FAILs on Solaris

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103407

--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Created attachment 52501
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=52501&action=edit
Patch to fix abi-check on Solaris 11.3

This patch changes the version of the std::from_chars symbols from 
GLIBCXX_3.4.29 to GLIBCXX_3.4.30 for targets where they were absent in gcc-11
and are present in gcc-12 (such as Solaris 11.3).

It also adds aliases for Solaris 11.4 (and later) so that they are present with
both symbol versions, to support executables linked on Solaris 11.3 and
expecting the symbols to have the new version.

[Bug libstdc++/103407] [12 regression] abi_check FAILs on Solaris

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103407

--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> ---
This fixes the abi check FAIL on Solaris 11.3, I don't have access to 11.4 to
try it.

[Bug libstdc++/103407] [12 regression] abi_check FAILs on Solaris

[ro at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103407

--- Comment #7 from Rainer Orth <ro at gcc dot gnu.org> ---
EWRONGPATCH?  I'll give it a whirl on both 11.3 and 11.4 then.

[Bug libstdc++/103407] [12 regression] abi_check FAILs on Solaris

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103407

--- Comment #8 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Oh dear, yes, wrong patch. I'll attach the right one in a few hours.

[Bug libstdc++/103407] [12 regression] abi_check FAILs on Solaris

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103407

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #52501|0                           |1
        is obsolete|                            |

--- Comment #9 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Created attachment 52504
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=52504&action=edit
Correct patch for this bug

[Bug libstdc++/103407] [12 regression] abi_check FAILs on Solaris

[ro at CeBiTec dot Uni-Bielefeld.DE]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103407

--- Comment #10 from ro at CeBiTec dot Uni-Bielefeld.DE <ro at CeBiTec dot Uni-Bielefeld.DE> ---
> --- Comment #8 from Jonathan Wakely <redi at gcc dot gnu.org> ---
> Oh dear, yes, wrong patch. I'll attach the right one in a few hours.

I've now managed to test it on both Solaris 11.3 and 11.4.  However, it
didn't work on 11.4 and in hindsight it's clear why not:
_GLIBCXX_HAVE_SYMVER_SYMBOL_RENAMING_RUNTIME_SUPPORT is always 0 on
Solaris, as explained in this snippet from acinclude.m4:

     # The Solaris 2 runtime linker doesn't support the GNU extension of
     # binding the same symbol to different versions

[Bug libstdc++/103407] [12 regression] abi_check FAILs on Solaris

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103407

--- Comment #11 from Jonathan Wakely <redi at gcc dot gnu.org> ---
OK, so we can just drop the alias symbols. But that means that libstdc++.so on
Solaris 11.3 and 11.4 will be incompatible. Is that acceptable?

If not, maybe the right thing to do is just add the symbols to GLIBCXX_3.4.29
for Solaris 11.3 as well, for consistency with the library on 11.4

That would mean that libstdc++.so.6.0.30 has symbols in the GLIBCXX_3.4.29
version that weren't in libstdc++.6.0.29

[Bug libstdc++/103407] [12 regression] abi_check FAILs on Solaris

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103407

--- Comment #12 from Jonathan Wakely <redi at gcc dot gnu.org> ---
I tried this instead, but I think this still counts as "binding the same symbol
to different versions", and didn't work:

#if defined __sun__ && defined _GLIBCXX_HAVE_USELOCALE
#if defined(_GLIBCXX_SYMVER_SUN) && defined(_GLIBCXX_SHARED) \
    && defined(_GLIBCXX_HAVE_AS_SYMVER_DIRECTIVE)
// Solaris 11.4 supports uselocale, so std::from_chars is present since gcc-11
// with symbol version GLIBCXX_3.4.29. Solaris 11.3 does not support uselocale
// so std::from_chars is not present until gcc-12, with version GLIBCXX_3.4.30.
// Define aliases so that code linked on Solaris 11.3 runs on 11.4 too.
from_chars_result
__from_chars_compat(const char* first, const char* last,
                    double& value, chars_format fmt) noexcept
{ return std::from_chars(first, last, value, fmt); }
asm(".symver _ZSt19__from_chars_compatPKcS0_RdSt12chars_format,
_ZSt10from_charsPKcS0_RdSt12chars_formaT@GLIBCXX_3.4.30");
from_chars_result
__from_chars_compat(const char* first, const char* last,
                    long double& value, chars_format fmt) noexcept
{ return std::from_chars(first, last, value, fmt); }
asm(".symver _ZSt19__from_chars_compatPKcS0_ReSt12chars_format,
_ZSt10from_charsPKcS0_ReSt12chars_formaT@GLIBCXX_3.4.30");
from_chars_result
__from_chars_compat(const char* first, const char* last,
                    float& value, chars_format fmt) noexcept
{ return std::from_chars(first, last, value, fmt); }
asm(".symver _ZSt19__from_chars_compatPKcS0_RfSt12chars_format,
_ZSt10from_charsPKcS0_RfSt12chars_formaT@GLIBCXX_3.4.30");
#endif
#endif

This does get compiled, but I don't see those @GLIBCXX_3.4.30 symbols in the
DSO. Maybe I'm missing something that would make them exported as global
symbols, or maybe this just can't be done on Solaris.

[Bug libstdc++/103407] [12 regression] abi_check FAILs on Solaris

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103407

--- Comment #13 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jonathan Wakely <redi@gcc.gnu.org>:

https://gcc.gnu.org/g:2f26b26721d5f8a6ac874fc23e18e1b03d207990

commit r12-7679-g2f26b26721d5f8a6ac874fc23e18e1b03d207990
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Wed Mar 16 20:35:47 2022 +0000

    libstdc++: Fix symbol versioning for Solaris 11.3 [PR103407]

    The new std::from_chars implementation means that those symbols are now
    defined on Solaris 11.3, which lacks uselocale. They were not present in
    gcc-11, but the linker script gives them the GLIBCXX_3.4.29 symbol
    version because that is the version where they appeared for systems with
    uselocale.

    This makes the version for those symbols depend on whether uselocale is
    available or not, so that they get version GLIBCXX_3.4.30 on targets
    where they weren't defined in gcc-11.

    In order to avoid needing separate ABI baseline files for Solaris 11.3
    and 11.4, the ABI checker program now treats the floating-point
    std::from_chars overloads as undesignated if they are not found in the
    baseline symbols file. This means they can be left out of the SOlaris
    baseline without causing the check-abi target to fail.

    libstdc++-v3/ChangeLog:

            PR libstdc++/103407
            * config/abi/pre/gnu.ver: Make version for std::from_chars
            depend on HAVE_USELOCALE macro.
            * testsuite/util/testsuite_abi.cc (compare_symbols): Treat
            std::from_chars for floating-point types as undesignated if
            not found in the baseline symbols file.

[Bug libstdc++/103407] [12 regression] abi_check FAILs on Solaris

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103407

Jonathan Wakely <redi at gcc dot gnu.org> changed:

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

--- Comment #14 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Rainer confirmed on the mailing list that this is fixed.

[Bug libstdc++/103407] [12 regression] abi_check FAILs on Solaris

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103407

--- Comment #15 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Rainer Orth <ro@gcc.gnu.org>:

https://gcc.gnu.org/g:8c465ddd619bbb2949bc2bc31629c2a826a7c437

commit r13-39-g8c465ddd619bbb2949bc2bc31629c2a826a7c437
Author: Rainer Orth <ro@CeBiTec.Uni-Bielefeld.DE>
Date:   Fri Apr 29 13:44:49 2022 +0200

    libstdc++: Update Solaris baselines for GCC 12.1

    The following patch updates the Solaris baselines for GCC 12.1.

    Tested on i386-pc-solaris2.11 and sparc-sun-solaris2.11 (Solaris 11.3
    and 11.4 in each case).

    The only (expected) difference between the 11.3 and 11.4 versions is

    --- baseline_symbols.txt.s113s  2022-04-28 10:37:11.464068450 +0000
    +++ baseline_symbols.txt.s114s  2022-04-27 16:54:31.995636805 +0000
    @@ -4070,3 +4070,3 @@
    -FUNC:_ZSt10from_charsPKcS0_RdSt12chars_format@@GLIBCXX_3.4.30
    -FUNC:_ZSt10from_charsPKcS0_ReSt12chars_format@@GLIBCXX_3.4.30
    -FUNC:_ZSt10from_charsPKcS0_RfSt12chars_format@@GLIBCXX_3.4.30
    +FUNC:_ZSt10from_charsPKcS0_RdSt12chars_format@@GLIBCXX_3.4.29
    +FUNC:_ZSt10from_charsPKcS0_ReSt12chars_format@@GLIBCXX_3.4.29
    +FUNC:_ZSt10from_charsPKcS0_RfSt12chars_format@@GLIBCXX_3.4.29

    which is handled by the fix for PR libstdc++/103407.  I'm using the 11.4
    version here.


    2022-04-27  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>

            libstdc++-v3:
            * config/abi/post/i386-solaris/baseline_symbols.txt: Regenerate.
            * config/abi/post/i386-solaris/amd64/baseline_symbols.txt:
            Likewise.
            * config/abi/post/sparc-solaris/baseline_symbols.txt: Likewise.
            * config/abi/post/sparc-solaris/sparcv9/baseline_symbols.txt:
            Likewise.

[Bug libstdc++/103407] [12 regression] abi_check FAILs on Solaris

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103407

--- Comment #16 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-12 branch has been updated by Rainer Orth <ro@gcc.gnu.org>:

https://gcc.gnu.org/g:c733f40f87bdb414b3e99814d97946bad89db743

commit r12-8320-gc733f40f87bdb414b3e99814d97946bad89db743
Author: Rainer Orth <ro@CeBiTec.Uni-Bielefeld.DE>
Date:   Fri Apr 29 13:56:09 2022 +0200

    libstdc++: Update Solaris baselines for GCC 12.1

    The following patch updates the Solaris baselines for GCC 12.1.

    Tested on i386-pc-solaris2.11 and sparc-sun-solaris2.11 (Solaris 11.3
    and 11.4 in each case).

    The only (expected) difference between the 11.3 and 11.4 versions is

    --- baseline_symbols.txt.s113s  2022-04-28 10:37:11.464068450 +0000
    +++ baseline_symbols.txt.s114s  2022-04-27 16:54:31.995636805 +0000
    @@ -4070,3 +4070,3 @@
    -FUNC:_ZSt10from_charsPKcS0_RdSt12chars_format@@GLIBCXX_3.4.30
    -FUNC:_ZSt10from_charsPKcS0_ReSt12chars_format@@GLIBCXX_3.4.30
    -FUNC:_ZSt10from_charsPKcS0_RfSt12chars_format@@GLIBCXX_3.4.30
    +FUNC:_ZSt10from_charsPKcS0_RdSt12chars_format@@GLIBCXX_3.4.29
    +FUNC:_ZSt10from_charsPKcS0_ReSt12chars_format@@GLIBCXX_3.4.29
    +FUNC:_ZSt10from_charsPKcS0_RfSt12chars_format@@GLIBCXX_3.4.29

    which is handled by the fix for PR libstdc++/103407.  I'm using the 11.4
    version here.


    2022-04-27  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>

            libstdc++-v3:
            * config/abi/post/i386-solaris/baseline_symbols.txt: Regenerate.
            * config/abi/post/i386-solaris/amd64/baseline_symbols.txt:
            Likewise.
            * config/abi/post/sparc-solaris/baseline_symbols.txt: Likewise.
            * config/abi/post/sparc-solaris/sparcv9/baseline_symbols.txt:
            Likewise.