[Bug c++/42748] New: excess errors in testsuite runs (the mangling of 'va_list' has changed in GCC 4.4)

[Bug c++/42748] New: excess errors in testsuite runs (the mangling of 'va_list' has changed in GCC 4.4)

[doko at ubuntu dot com]

see http://gcc.gnu.org/ml/gcc-patches/2010-01/msg00670.html and followups. seen
on the gcc-4_4-branch and the trunk, glibc version is eglibc-2.11.1

when running the libstdc++v3 testsuite on arm-linux-gnueabi, a lot of test
cases fail with excess errors, e.g.

  FAIL: 17_intro/using_namespace_std_tr1_neg.cc (test for excess errors)

Excess errors:
In file included from
/home/doko/gcc/4.4/gcc-4.4-4.4.2/build/arm-linux-gnueabi/libstdc++-v3/include/bits/basic_string.h:2562,
                 from
/home/doko/gcc/4.4/gcc-4.4-4.4.2/build/arm-linux-gnueabi/libstdc++-v3/include/string:53,
                 from
/home/doko/gcc/4.4/gcc-4.4-4.4.2/build/arm-linux-gnueabi/libstdc++-v3/include/bitset:49,
                 from
/home/doko/gcc/4.4/gcc-4.4-4.4.2/src/libstdc++-v3/testsuite/17_intro/using_namespace_std_tr1_neg.cc:23:
/home/doko/gcc/4.4/gcc-4.4-4.4.2/build/arm-linux-gnueabi/libstdc++-v3/include/ext/string_conversions.h:
In instantiation of '_String __gnu_cxx::__to_xstring(int (*)(_CharT*, size_t,
const _CharT*, __va_list), size_t, const _CharT*, ...) [with _String =
std::basic_string<char, std::char_traits<char>, std::allocator<char> >, _CharT
= char]':
/home/doko/gcc/4.4/gcc-4.4-4.4.2/build/arm-linux-gnueabi/libstdc++-v3/include/bits/basic_string.h:2610:
  instantiated from here
/home/doko/gcc/4.4/gcc-4.4-4.4.2/build/arm-linux-gnueabi/libstdc++-v3/include/ext/string_conversions.h:90:
note: the mangling of 'va_list' has changed in GCC 4.4

http://launchpadlibrarian.net/37789038/buildlog_ubuntu-lucid-armel.gcc-snapshot_20100109-0ubuntu2_FULLYBUILT.txt.gz


-- 
           Summary: excess errors in testsuite runs (the mangling of
                    'va_list' has changed in GCC 4.4)
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: doko at ubuntu dot com
GCC target triplet: arm-linux-gnueabi


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[paolo dot carlini at oracle dot com]

------- Comment #1 from paolo dot carlini at oracle dot com  2010-01-14 18:26 -------
Mark, can you have a look to this issue, thanks!


-- 

paolo dot carlini at oracle dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |mark at codesourcery dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[mmitchel at gcc dot gnu dot org]

------- Comment #2 from mmitchel at gcc dot gnu dot org  2010-01-14 19:22 -------
Paolo --

I think that the warning is accurate; the mangling of va_list has indeed
changed on ARM in GCC 4.4 in order to conform to the ARM ABI specifications. 
There is an option to turn off warnings about PSABI issues; -Wno-psabi.  I
think that option (if not some stronger option) should be used.

Oh, wait.  Maybe we should not warn about this in a system header.  That's
probably the right choice and a trivial change to arm_mangle_type.

Do you agree?

-- Mark


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[paolo dot carlini at oracle dot com]

------- Comment #3 from paolo dot carlini at oracle dot com  2010-01-14 20:31 -------
Indeed. Matthias filed the PR and then I only changed the Summary to better
clarify that the point is simply not warning, *ever*, in system headers. Nice
that you agree about that analysis of mine and that a fix seems easy ;)


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[mmitchel at gcc dot gnu dot org]

------- Comment #4 from mmitchel at gcc dot gnu dot org  2010-01-15 00:17 -------
OK, I will fix this one.


-- 

mmitchel at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |mark at codesourcery dot com
                   |dot org                     |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[ramana at gcc dot gnu dot org]

-- 

ramana at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2010-01-15 09:56:23
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[mmitchel at gcc dot gnu dot org]

------- Comment #5 from mmitchel at gcc dot gnu dot org  2010-01-25 03:14 -------
Subject: Bug 42748

Author: mmitchel
Date: Mon Jan 25 03:14:25 2010
New Revision: 156202

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=156202
Log:
        PR c++/42748
        * config/arm/arm.c (arm_mangle_type): Do not warn about changes to
        mangling of va_list in system headers.

        PR c++/42748
        * g++.dg/abi/arm_va_list2.C: New test.
        * g++.dg/abi/arm_va_list2.h: Companion header file.

Added:
    trunk/gcc/testsuite/g++.dg/abi/arm_va_list2.C
    trunk/gcc/testsuite/g++.dg/abi/arm_va_list2.h
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/config/arm/arm.c
    trunk/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[mmitchel at gcc dot gnu dot org]

------- Comment #6 from mmitchel at gcc dot gnu dot org  2010-01-25 03:16 -------
Fixed.


-- 

mmitchel at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[paolo dot carlini at oracle dot com]

-- 

paolo dot carlini at oracle dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.5.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[doko at ubuntu dot com]

------- Comment #7 from doko at ubuntu dot com  2010-01-27 14:21 -------
please consider a backport for the 4.4 branch


-- 

doko at ubuntu dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |REOPENED
      Known to fail|                            |4.4.3
      Known to work|                            |4.5.0
         Resolution|FIXED                       |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[paolo dot carlini at oracle dot com]

------- Comment #8 from paolo dot carlini at oracle dot com  2010-01-27 14:52 -------
If you say 'consider' and are talking to a GWP and release manager, it seems
unpolite to re-open at once.


-- 

paolo dot carlini at oracle dot com changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[mark at codesourcery dot com]

------- Comment #9 from mark at codesourcery dot com  2010-01-27 20:04 -------
Subject: Re:  warnings about 'mangling of 'va_list' has changed
 in GCC 4.4' not suppressed in sytem headers

paolo dot carlini at oracle dot com wrote:

> If you say 'consider' and are talking to a GWP and release manager, it seems
> unpolite to re-open at once.

I certainly took no offense.

I do think the patch would apply easily to GCC 4.4, and I think it's
appropriate to apply it there.  However, I have so little bandwidth for
GCC development these days that I will not be able to quickly do the
appropriate patch/test cycle.

Matthias, would you like to do that?  If so, the patch is certainly
pre-approved.  If not, I'll put it in my queue, but please be patient.

Thanks,


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[doko at ubuntu dot com]

------- Comment #10 from doko at ubuntu dot com  2010-01-27 20:25 -------
I didn't intend to be inpolite.

Currently running a test build; will commit if the build succeeds without
regressions.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[paolo dot carlini at oracle dot com]

------- Comment #11 from paolo dot carlini at oracle dot com  2010-01-27 21:24 -------
Actually, the preferred spelling is impolite, thus neither unpolite, nor
inpolite ;) Anyway, IMVHO the patch is really safe, thus, great that Matthias
can do the backport.

In general, I just *hate* these quick reopenings after somebody knowledgeable
has closed an issue for a reason.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[doko at ubuntu dot com]

------- Comment #12 from doko at ubuntu dot com  2010-01-29 08:37 -------
checked the patch on the 4.4 branch; the error message for the test case in the
original report is gone, but there are some warnings about the mangling in the
libstdc++ files as well. not reopening yet, as I didn't check a build on the
trunk yet.

/home/doko/gcc/4.4/gcc-4.4-4.4.3/src/libstdc++-v3/testsuite/18_support/exception
_ptr/rethrow_exception.cc:114: note: the mangling of 'va_list' has changed in
GC
C 4.4
output is:
/home/doko/gcc/4.4/gcc-4.4-4.4.3/src/libstdc++-v3/testsuite/18_support/exception
_ptr/rethrow_exception.cc:114: note: the mangling of 'va_list' has changed in
GC
C 4.4

FAIL: 18_support/exception_ptr/rethrow_exception.cc (test for excess errors)

/home/doko/gcc/4.4/gcc-4.4-4.4.3/src/libstdc++-v3/testsuite/19_diagnostics/error
_category/cons/default.cc:33: note: the mangling of 'va_list' has changed in
GCC
 4.4
output is:
/home/doko/gcc/4.4/gcc-4.4-4.4.3/src/libstdc++-v3/testsuite/19_diagnostics/error
_category/cons/default.cc:33: note: the mangling of 'va_list' has changed in
GCC
 4.4

FAIL: 19_diagnostics/error_category/cons/default.cc (test for excess errors)
/home/doko/gcc/4.4/gcc-4.4-4.4.3/src/libstdc++-v3/testsuite/19_diagnostics/error
_category/operators/equal.cc:34: note: the mangling of 'va_list' has changed in 
GCC 4.4

FAIL: 19_diagnostics/error_code/cons/1.cc (test for excess errors)
Excess errors:
/home/doko/gcc/4.4/gcc-4.4-4.4.3/src/libstdc++-v3/testsuite/19_diagnostics/error_code/cons/1.cc:45:
note: the mangling of 'va_list' has changed in GCC 4.4


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[manu at gcc dot gnu dot org]

------- Comment #13 from manu at gcc dot gnu dot org  2010-01-29 13:09 -------
Why is this a note and not simply a warning? Anyway, in_system_header should
slowly go away, either use diagnostic_report_warnings_p (input_location) or
in_system_header_at (input_location). None of them is necessary if you just
used warning(OPT_Wpsabi,).


-- 

manu at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |manu at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[paolo dot carlini at oracle dot com]

------- Comment #14 from paolo dot carlini at oracle dot com  2010-01-29 13:40 -------
I can see that exception_ptr.h doesn't have the system header pragma, I think
on purpose, some time ago we briefly discussed that and decided to not add it
to the libsupc++ user-visible headers, if possible. <system_error> however
*does* have it, thus, if there are problems with it in mainline, it's because
inform do not behave exactly like normal warnings, I think Joseph warned us
about that...

In general, I would say Manuel has very good points about this issue.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[mark at codesourcery dot com]

------- Comment #15 from mark at codesourcery dot com  2010-01-29 15:12 -------
Subject: Re:  warnings about 'mangling of 'va_list' has changed
 in GCC 4.4' not suppressed in sytem headers

manu at gcc dot gnu dot org wrote:

> Why is this a note and not simply a warning?

Because, as noted earlier, it's not reflective of any likely problem in
the user's code.  I think a warning is appropriate if the compiler
detects something which might indicate a bug in the application, but
this is just the compiler telling you about that something might go
wrong if you linked with code form a different version of G++.  Which is
unlikely, and might go wrong for other reasons too.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[mmitchel at gcc dot gnu dot org]

------- Comment #16 from mmitchel at gcc dot gnu dot org  2010-02-18 04:40 -------
Paolo --

I don't understand why all libstdc++ headers should not have #pragma GCC
system_header in them.  Would you please explain that?

I think there's a semantic hair that we could split about whether they are
"system" headers or "compiler" headers, but in either case, we never want to
warn about them.  If we made this note into a warning, we would still warn
because we would still see that this is not a system header.

Thanks,

-- Mark


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[paolo dot carlini at oracle dot com]

------- Comment #17 from paolo dot carlini at oracle dot com  2010-02-18 09:36 -------
(In reply to comment #16)
> I don't understand why all libstdc++ headers should not have #pragma GCC
> system_header in them.  Would you please explain that?

Hi Mark. For sure all the *library proper* headers should have (and afaik, have
already) the pragma. If I understand correctly, the doubt is about the
libsupc++ headers: at some point in the past we discussed that briefly and we
came to the conclusion that if we could avoid decorating those too it would be
cleaner (Gaby agreed, I'm 100% sure). But indeed, nothing set in stone, at
least for 4.5.x, if we want to decorate the few user visibile headers in
libsupc++, I do not object.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[mmitchel at gcc dot gnu dot org]

------- Comment #18 from mmitchel at gcc dot gnu dot org  2010-02-18 15:13 -------
Paolo --

I think libsupc++ is just as much a "system library" as libstdc++.  It doesn't
have an ISO-standard API, of course, but that's not the point; it's just as
much a part of the system/implementation as libstdc++.  To the extent a program
is going to use a header that we ship from libsupc++, that program certainly
doesn't want to get random warnings about those headers. 

However, Julian Brown warns me that he's been playing with this and that it
doesn't entirely solve the problem.  It may be that my earlier patch to arm.c
is insufficient in some cases.  So, I'd like the libstdc++ maintainers to make
the change to the libsupc++ headers -- unless someone can articulate a good
reason not to do so of course -- but there may still be more work to do.  We
will continue to investigate the possible non-workingness of the patch.

Thanks,

-- Mark


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[paolo dot carlini at oracle dot com]

------- Comment #19 from paolo dot carlini at oracle dot com  2010-02-18 15:24 -------
Ok, it's just an handful of files, after all. If Julian wants to add the
pragmas, the change is pre-approved, otherwise, just let me know when you have
the other issues under control, and I'll do it.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[manu at gcc dot gnu dot org]

------- Comment #20 from manu at gcc dot gnu dot org  2010-02-18 19:44 -------
(In reply to comment #15)
> Subject: Re:  warnings about 'mangling of 'va_list' has changed
>  in GCC 4.4' not suppressed in sytem headers
> 
> manu at gcc dot gnu dot org wrote:
> 
> > Why is this a note and not simply a warning?
> 
> Because, as noted earlier, it's not reflective of any likely problem in
> the user's code.  I think a warning is appropriate if the compiler
> detects something which might indicate a bug in the application, but
> this is just the compiler telling you about that something might go
> wrong if you linked with code form a different version of G++.  Which is
> unlikely, and might go wrong for other reasons too.

So it is the compiler telling you that something might go wrong and you can
silence it with -Wno-psabi, which is a warning option. Moreover, as it stands
now, if someone has -Werror=psabi, the compilation will not stop and they might
get bitten by this. Moreover2, -w will not silence the note.  I still
completely fail to see why it is a note and not a warning.

In any case, using diagnostic_report_warnings_p (location) should fix it.


-- 

manu at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|manu at gcc dot gnu dot org |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[mark at codesourcery dot com]

------- Comment #21 from mark at codesourcery dot com  2010-02-18 19:47 -------
Subject: Re:  warnings about 'mangling of 'va_list' has changed
 in GCC 4.4' not suppressed in sytem headers

manu at gcc dot gnu dot org wrote:

> In any case, using diagnostic_report_warnings_p (location) should fix it.

AFAICT, this is not the case; at the point of mangling, input_location
does not necessarily reflect the location at which the function was
declared.  Julian Brown and I are looking into this.

Thanks,


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[mmitchel at gcc dot gnu dot org]

------- Comment #22 from mmitchel at gcc dot gnu dot org  2010-02-28 17:08 -------
Subject: Bug 42748

Author: mmitchel
Date: Sun Feb 28 17:07:54 2010
New Revision: 157124

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=157124
Log:
2010-02-27  Mark Mitchell  <mark@codesourcery.com>

        PR c++/42748
        * cp-tree.h (push_tinst_level): Declare.
        (pop_tinst_level): Likewise.
        * pt.c (push_tinst_level): Give it external linkage.
        (pop_tinst_level): Likewise.
        * mangle.c (mangle_decl_string): Set the source location to that
        of the decl while mangling.

2010-02-27  Mark Mitchell  <mark@codesourcery.com>

        PR c++/42748
        * g++.dg/abi/mangle11.C: Adjust mangling warning locations.
        * g++.dg/abi/mangle12.C: Likewise.
        * g++.dg/abi/mangle20-2.C: Likewise.
        * g++.dg/abi/mangle17.C: Likewise.
        * g++.dg/template/cond2.C: Likewise.
        * g++.dg/template/pr35240.C: Likewise.

Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/cp-tree.h
    trunk/gcc/cp/mangle.c
    trunk/gcc/cp/pt.c
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/g++.dg/abi/mangle11.C
    trunk/gcc/testsuite/g++.dg/abi/mangle12.C
    trunk/gcc/testsuite/g++.dg/abi/mangle17.C
    trunk/gcc/testsuite/g++.dg/abi/mangle20-2.C
    trunk/gcc/testsuite/g++.dg/template/cond2.C
    trunk/gcc/testsuite/g++.dg/template/pr35240.C


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748

[Bug c++/42748] warnings about 'mangling of 'va_list' has changed in GCC 4.4' not suppressed in sytem headers

[dominiq at lps dot ens dot fr]

------- Comment #23 from dominiq at lps dot ens dot fr  2010-03-01 10:20 -------
*** Bug 40459 has been marked as a duplicate of this bug. ***


-- 

dominiq at lps dot ens dot fr changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |dominiq at lps dot ens dot
                   |                            |fr


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42748