[Bug libstdc++/66146] call_once not C++11-compliant on ppc64le

[cohenjon at google dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66146

Jon Cohen  changed:

   What|Removed |Added

 CC||cohenjon at google dot com

--- Comment #21 from Jon Cohen  ---
What is the current status on this bug?  I'm currently working on exception
safety for Abseil's call_once which uses pthread_once under the hood.  It looks
like there are still people bringing up issue with this in the glibc thread as
well -- is this still actively being worked on?

[Bug libstdc++/83658] New: any::emplace deletes invalid memory when an overloaded operator new() throws

[cohenjon at google dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83658

Bug ID: 83658
   Summary: any::emplace deletes invalid memory when an overloaded
operator new() throws
   Product: gcc
   Version: 8.0
Status: UNCONFIRMED
  Severity: normal
  Priority: P3
 Component: libstdc++
  Assignee: unassigned at gcc dot gnu.org
  Reporter: cohenjon at google dot com
  Target Milestone: ---

Note the following Wandbox: https://wandbox.org/permlink/1emVGP0a09lmd4g2 --
the std::any is still empty after new() throws and so the destructor should be
a no-op.  Instead it calls delete().

__do_emplace sets the manager pointer before attempting to create a new object.
 When new() throws after calling reset(), _M_ptr doesn't point to valid memory.
 When, later, the destructor is called on the any, the manager pointer still is
non-null, so the destructor, via reset(), will trigger the call to
_S_manage(_Op_destroy, ...), calling delete on the invalid _M_ptr.  

I believe setting the manager pointer after calling _S_create() will fix the
issue, since the manager pointer will still be null after _S_create_ propagates
the exception.

[Bug libstdc++/66146] call_once not C++11-compliant on ppc64le

[cohenjon at google dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66146

--- Comment #24 from Jon Cohen  ---
I don't see anything in the release notes about call_once.  Is this still an
open issue?