[Bug libstdc++/98613] New: vstring mov testsuite failures on AIX

[Bug libstdc++/98613] New: vstring mov testsuite failures on AIX

[dje at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98613

            Bug ID: 98613
           Summary: vstring mov testsuite failures on AIX
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: dje at gcc dot gnu.org
  Target Milestone: ---

/tmp/GCC/powerpc-ibm-aix7.2.3.0/libstdc++-v3/include/ext/new_allocator.h:139:
warning: 'void operator delete(void*, std::size_t)' called on unallocated
object '__gnu_cxx::__rc_string_base<char, std::char_traits<char>,
std::allocator<char> > ::_S_empty_rep' [-Wfree-nonheap-object]
/tmp/GCC/powerpc-ibm-aix7.2.3.0/libstdc++-v3/include/ext/new_allocator.h:139:
warning: 'void operator delete(void*, std::size_t)' called on unallocated
object '__gnu_cxx::__rc_string_base<char, std::char_traits<char>,
std::allocator<char> >
::_S_empty_rep' [-Wfree-nonheap-object]

more extensive message:

In member function 'void __gnu_cxx::new_allocator<_Tp>::deallocate(_Tp*,
__gnu_c
xx::new_allocator<_Tp>::size_type) [with _Tp =
__gnu_cxx::__rc_string_base<char,
 std::char_traits<char>, std::allocator<char> >::_Rep]',
    inlined from 'void __gnu_cxx::__rc_string_base<_CharT, _Traits,
_Alloc>::_Re
p::_M_destroy(const _Alloc&) [with _CharT = char; _Traits =
std::char_traits<cha
r>; _Alloc = std::allocator<char>]' at
/tmp/GCC/powerpc-ibm-aix7.2.3.0/libstdc++
-v3/include/ext/rc_string_base.h:455,
    inlined from 'void __gnu_cxx::__rc_string_base<_CharT, _Traits,
_Alloc>::_M_
dispose() [with _CharT = char; _Traits = std::char_traits<char>; _Alloc =
std::a
llocator<char>]' at
/tmp/GCC/powerpc-ibm-aix7.2.3.0/libstdc++-v3/include/ext/rc_
string_base.h:212,
    inlined from '__gnu_cxx::__rc_string_base<_CharT, _Traits,
_Alloc>::~__rc_st
ring_base() [with _CharT = char; _Traits = std::char_traits<char>; _Alloc =
std:
:allocator<char>]' at
/tmp/GCC/powerpc-ibm-aix7.2.3.0/libstdc++-v3/include/ext/r
c_string_base.h:332,
    inlined from '__gnu_cxx::__versa_string<_CharT, _Traits, _Alloc,
_Base>::~__
versa_string() [with _CharT = char; _Traits = std::char_traits<char>; _Alloc =
s
td::allocator<char>; _Base = __gnu_cxx::__rc_string_base]' at
/tmp/GCC/powerpc-i
bm-aix7.2.3.0/libstdc++-v3/include/ext/vstring.h:250,
    inlined from 'void test02()' at
/nasfarm/edelsohn/src/src/libstdc++-v3/tests
uite/ext/vstring/modifiers/assign/move_assign.cc:39:
/tmp/GCC/powerpc-ibm-aix7.2.3.0/libstdc++-v3/include/ext/new_allocator.h:139:
wa
rning: 'void operator delete(void*, std::size_t)' called on unallocated object
'
__gnu_cxx::__rc_string_base<char, std::char_traits<char>, std::allocator<char>
>
::_S_empty_rep' [-Wfree-nonheap-object]

[Bug libstdc++/98613] vstring mov testsuite failures on AIX

[dje at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98613

David Edelsohn <dje at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
             Target|                            |powerpc-ibm-aix*
   Last reconfirmed|                            |2021-01-10
             Status|UNCONFIRMED                 |NEW

--- Comment #1 from David Edelsohn <dje at gcc dot gnu.org> ---
Confirmed.

[Bug libstdc++/98613] vstring mov testsuite failures on AIX

[dje at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98613

--- Comment #2 from David Edelsohn <dje at gcc dot gnu.org> ---
These failures appeared with Martin Sebor's

[Bug libstdc++/98613] vstring mov testsuite failures on AIX

[dje at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98613

David Edelsohn <dje at gcc dot gnu.org> changed:

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

--- Comment #3 from David Edelsohn <dje at gcc dot gnu.org> ---
FAIL: ext/vstring/cons/moveable.cc (test for excess errors)
FAIL: ext/vstring/modifiers/assign/move_assign.cc (test for excess errors)

These failures appeared with Martin Sebor's fixes to -Wmismatched-new-delete on
2020-12-14.

Do these testcases need the same "Suppress false positive warning" changes, at
least for AIX?

[Bug libstdc++/98613] vstring mov testsuite failures on AIX

[msebor at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98613

Martin Sebor <msebor at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |diagnostic

--- Comment #4 from Martin Sebor <msebor at gcc dot gnu.org> ---
Yes, I think so.  I see code in the optimized dump that the warning should
trigger for even on x86_64 but doesn't due to a known bug/limitation in how GCC
determines the context into which a function defined in a system header has
been inlined.  All the calls to operator delete with _S_empty_rep should
trigger it:

$ /build/gcc-master/gcc/xg++ -B /build/gcc-master/gcc -nostdinc++ -I
/build/gcc-master/x86_64-pc-linux-gnu/libstdc++-v3/include/x86_64-pc-linux-gnu
-I /build/gcc-master/x86_64-pc-linux-gnu/libstdc++-v3/include -I
/src/gcc/master/libstdc++-v3/libsupc++ -I
/src/gcc/master/libstdc++-v3/include/backward -I
/src/gcc/master/libstdc++-v3/testsuite/util -L
/build/gcc-master/x86_64-pc-linux-gnu/libstdc++-v3/src/.libs -O3 -Wall
-fdump-tree-optimized=/dev/stdout
/src/gcc/master/libstdc++-v3/testsuite/ext/vstring/cons/moveable.cc | grep
delete
  operator delete (_17, _21); [tail call]
  operator delete (_35, _37);
  operator delete (_38, _40);
  operator delete (&MEM <struct _Rep> [(void *)&_S_empty_rep], _156);
  operator delete (_220, _224);
  operator delete (_288, _292);
  operator delete (_318, _322);
  operator delete (&MEM <struct _Rep> [(void *)&_S_empty_rep], _328);
  operator delete (&MEM <struct _Rep> [(void *)&_S_empty_rep], _334); [tail
call]

[Bug libstdc++/98613] vstring mov testsuite failures on AIX

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98613

--- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by David Edelsohn <dje@gcc.gnu.org>:

https://gcc.gnu.org/g:4a1d7f7e203d0ec4b9d67ea6fc9b84bee1e211d3

commit r11-6573-g4a1d7f7e203d0ec4b9d67ea6fc9b84bee1e211d3
Author: David Edelsohn <dje.gcc@gmail.com>
Date:   Sun Jan 10 18:10:34 2021 -0500

    libstdc++: Suppress more vstring testsuite warnings. [PR 98613]

        PR c++/57111 - 57111 - Generalize -Wfree-nonheap-object to delete

    can create false positive warnings for vstring _S_empty_rep.

    This patch prunes the excess false positive warnings from two more
    testcases.

    libstdc++-v3/ChangeLog:

            PR libstdc++/98613
            * testsuite/ext/vstring/cons/moveable.cc: Suppress false positive
            warning.
            * testsuite/ext/vstring/modifiers/assign/move_assign.cc: Same.

[Bug libstdc++/98613] vstring mov testsuite failures on AIX

[dje at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98613

David Edelsohn <dje at gcc dot gnu.org> changed:

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

--- Comment #6 from David Edelsohn <dje at gcc dot gnu.org> ---
ignore the warnings.