[Bug libstdc++/120390] [12/13/14/15/16 Regression] Request to improve error with private destructor

2025-06-11 Thread cvs-commit at gcc dot gnu.org via Gcc-bugs 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120390

--- Comment #9 from GCC Commits  ---
The master branch has been updated by Jonathan Wakely :

https://gcc.gnu.org/g:01789efaea25a48ac45dae8facb6db8abd8ebb14

commit r16-1412-g01789efaea25a48ac45dae8facb6db8abd8ebb14
Author: Jonathan Wakely 
Date:   Wed May 21 23:48:34 2025 +0100

libstdc++: Improve diagnostics for ill-formed std::_Destroy and
std::_Destroy_n [PR120390]

By using std::is_trivially_destructible instead of the old
__has_trivial_destructor built-in we no longer need the static_assert to
deal with types with deleted destructors. All non-destructible types,
including those with deleted destructors, will now give user-friendly
diagnostics that clearly explain the problem.

Also combine the _Destroy_aux and _Destroy_n_aux class templates used
for C++98 into one, so that we perform fewer expensive class template
instantiations.

libstdc++-v3/ChangeLog:

PR libstdc++/120390
* include/bits/stl_construct.h (_Destroy_aux::__destroy_n): New
static member function.
(_Destroy_aux::__destroy_n): Likewise.
(_Destroy_n_aux): Remove.
(_Destroy(ForwardIterator, ForwardIterator)): Remove
static_assert. Use is_trivially_destructible instead of
__has_trivial_destructor.
(_Destroy_n): Likewise. Use _Destroy_aux::__destroy_n instead of
_Destroy_n_aux::__destroy_n.
*
testsuite/20_util/specialized_algorithms/memory_management_tools/destroy_neg.cc:
Adjust dg-error strings. Move destroy_n tests to ...
*
testsuite/20_util/specialized_algorithms/memory_management_tools/destroy_n_neg.cc:
New test.
* testsuite/23_containers/vector/cons/destructible_debug_neg.cc:
Adjust dg-error strings.
* testsuite/23_containers/vector/cons/destructible_neg.cc:
Likewise.

Reviewed-by: Tomasz KamiÅski

[Bug libstdc++/120390] [12/13/14/15/16 Regression] Request to improve error with private destructor

2025-06-10 Thread redi at gcc dot gnu.org via Gcc-bugs 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120390

Jonathan Wakely  changed:

   What|Removed |Added

   Keywords||patch

--- Comment #8 from Jonathan Wakely  ---
With https://gcc.gnu.org/pipermail/gcc-patches/2025-June/686306.html the
static_assert failure is replaced with:

/home/jwakely/gcc/16/include/c++/16.0.0/bits/stl_construct.h:166:22: error:
'MovieData::~MovieData()' is private within this context
  166 |   __pointer->~_Tp();
  |   ~~~^~
dest.cc:5:5: note: declared private here
5 | ~MovieData(){}
  | ^

[Bug libstdc++/120390] [12/13/14/15/16 Regression] Request to improve error with private destructor

2025-05-23 Thread redi at gcc dot gnu.org via Gcc-bugs 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120390

Jonathan Wakely  changed:

   What|Removed |Added

 Status|NEW |ASSIGNED
   Target Milestone|--- |12.5
  Known to fail||15.1.0, 7.5.0
   Priority|P3  |P4
   Severity|normal  |minor
   Assignee|unassigned at gcc dot gnu.org  |redi at gcc dot gnu.org
Summary|Request to improve error|[12/13/14/15/16 Regression]
   |with private destructor |Request to improve error
   ||with private destructor
  Known to work||6.5.0

--- Comment #7 from Jonathan Wakely  ---
I pulled at this thread and ended up unravelling parts of std::vector (Bug
94831, Bug 40192, Bug 120397)

I'm just going to make a minimal change for this which would be suitable for
backports, because this is a diagnostic regression. Then I'll rewrite
std::_Destroy and std::_Destroy_n on trunk, after deprecating support for
std::vector which should never have been supported in the first
place.