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* [Bug libstdc++/58659] New: Construction of shared_ptr from unique_ptr mismatches new/delete and std::allocator for __shared_ptr_count @ 2013-10-07 21:16 spencer at starscale dot com 2013-10-07 21:36 ` [Bug libstdc++/58659] " redi at gcc dot gnu.org ` (3 more replies) 0 siblings, 4 replies; 5+ messages in thread From: spencer at starscale dot com @ 2013-10-07 21:16 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58659 Bug ID: 58659 Summary: Construction of shared_ptr from unique_ptr mismatches new/delete and std::allocator for __shared_ptr_count Product: gcc Version: 4.8.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: libstdc++ Assignee: unassigned at gcc dot gnu.org Reporter: spencer at starscale dot com CC: jwakely.gcc at gmail dot com Using gcc-4.8.1 configured with --enable-threads=single --enable-libstdcxx-allocator=mt, I'm seeing the following tiny program crash: int main() { std::unique_ptr<X> u = std::unique_ptr<X>(new X); std::shared_ptr<X> s(std::move(u)); return 0; } Note that I am using a different default std::allocator base class (not new/delete). I think the bug is that the shared_ptr count object is being allocated with new and deleted with std::allocator. This will work when std::allocator is new/delete, but not otherwise. I haven't had time to prove it or work up a patch yet; I can if that helps: please let me know. Look at __shared_ptr_base's __S_create_from_up: template<typename _Tp, typename _Del> static _Sp_counted_base<_Lp>* _S_create_from_up(std::unique_ptr<_Tp, _Del>&& __r, typename std::enable_if<!std::is_reference<_Del>::value>::type* = 0) { typedef typename unique_ptr<_Tp, _Del>::pointer _Ptr; return new _Sp_counted_deleter<_Ptr, _Del, std::allocator<void>, _Lp>(__r.get(), __r.get_deleter()); } It always uses "new" to allocate an _Sp_counted_deleter (in both overloads). I think this is the bug, because _Sp_counted_deleter always uses std::allocator to dispose of itself: virtual void _M_destroy() noexcept { typedef typename allocator_traits<_Alloc>::template rebind_traits<_Sp_counted_deleter> _Alloc_traits; typename _Alloc_traits::allocator_type __a(_M_del); _Alloc_traits::destroy(__a, this); _Alloc_traits::deallocate(__a, this, 1); } CC Jonathan Wakely who has already analyzed this with a test case for the stock std::allocator on the mailing list. ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug libstdc++/58659] Construction of shared_ptr from unique_ptr mismatches new/delete and std::allocator for __shared_ptr_count 2013-10-07 21:16 [Bug libstdc++/58659] New: Construction of shared_ptr from unique_ptr mismatches new/delete and std::allocator for __shared_ptr_count spencer at starscale dot com @ 2013-10-07 21:36 ` redi at gcc dot gnu.org 2013-10-08 12:33 ` redi at gcc dot gnu.org ` (2 subsequent siblings) 3 siblings, 0 replies; 5+ messages in thread From: redi at gcc dot gnu.org @ 2013-10-07 21:36 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58659 Jonathan Wakely <redi at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |ASSIGNED Last reconfirmed| |2013-10-07 Assignee|unassigned at gcc dot gnu.org |redi at gcc dot gnu.org Target Milestone|--- |4.8.2 Ever confirmed|0 |1 --- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> --- Thanks for the report (it's easier to track and find in future if it's in bugzilla) I'll fix this asap. ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug libstdc++/58659] Construction of shared_ptr from unique_ptr mismatches new/delete and std::allocator for __shared_ptr_count 2013-10-07 21:16 [Bug libstdc++/58659] New: Construction of shared_ptr from unique_ptr mismatches new/delete and std::allocator for __shared_ptr_count spencer at starscale dot com 2013-10-07 21:36 ` [Bug libstdc++/58659] " redi at gcc dot gnu.org @ 2013-10-08 12:33 ` redi at gcc dot gnu.org 2013-10-08 13:38 ` redi at gcc dot gnu.org 2013-10-08 13:43 ` redi at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: redi at gcc dot gnu.org @ 2013-10-08 12:33 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58659 --- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> --- Author: redi Date: Tue Oct 8 12:33:37 2013 New Revision: 203274 URL: http://gcc.gnu.org/viewcvs?rev=203274&root=gcc&view=rev Log: PR libstdc++/58659 * include/bits/shared_ptr_base.h (__shared_count::__shared_count(P,D)): Delegate to constructor taking allocator. (__shared_count::_S_create_from_up): Inline into ... (__shared_count::__shared_count(unique_ptr<Y,D>&&): Here. Use std::conditional instead of constrained overloads. Allocate memory using the allocator type that will be used for deallocation. * testsuite/20_util/shared_ptr/cons/58659.cc: New. * testsuite/20_util/shared_ptr/cons/43820_neg.cc: Adjust. Added: trunk/libstdc++-v3/testsuite/20_util/shared_ptr/cons/58659.cc Modified: trunk/libstdc++-v3/ChangeLog trunk/libstdc++-v3/include/bits/shared_ptr_base.h trunk/libstdc++-v3/testsuite/20_util/shared_ptr/cons/43820_neg.cc ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug libstdc++/58659] Construction of shared_ptr from unique_ptr mismatches new/delete and std::allocator for __shared_ptr_count 2013-10-07 21:16 [Bug libstdc++/58659] New: Construction of shared_ptr from unique_ptr mismatches new/delete and std::allocator for __shared_ptr_count spencer at starscale dot com 2013-10-07 21:36 ` [Bug libstdc++/58659] " redi at gcc dot gnu.org 2013-10-08 12:33 ` redi at gcc dot gnu.org @ 2013-10-08 13:38 ` redi at gcc dot gnu.org 2013-10-08 13:43 ` redi at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: redi at gcc dot gnu.org @ 2013-10-08 13:38 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58659 --- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> --- Author: redi Date: Tue Oct 8 13:38:21 2013 New Revision: 203277 URL: http://gcc.gnu.org/viewcvs?rev=203277&root=gcc&view=rev Log: PR libstdc++/58659 * include/bits/shared_ptr_base.h (__shared_count::__shared_count(P,D)): Delegate to constructor taking allocator. (__shared_count::_S_create_from_up): Inline into ... (__shared_count::__shared_count(unique_ptr<Y,D>&&): Here. Use std::conditional instead of constrained overloads. Allocate memory using the allocator type that will be used for deallocation. * testsuite/20_util/shared_ptr/cons/58659.cc: New. * testsuite/20_util/shared_ptr/cons/43820_neg.cc: Adjust. Added: branches/gcc-4_8-branch/libstdc++-v3/testsuite/20_util/shared_ptr/cons/58659.cc Modified: branches/gcc-4_8-branch/libstdc++-v3/ChangeLog branches/gcc-4_8-branch/libstdc++-v3/include/bits/shared_ptr_base.h branches/gcc-4_8-branch/libstdc++-v3/testsuite/20_util/shared_ptr/cons/43820_neg.cc ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug libstdc++/58659] Construction of shared_ptr from unique_ptr mismatches new/delete and std::allocator for __shared_ptr_count 2013-10-07 21:16 [Bug libstdc++/58659] New: Construction of shared_ptr from unique_ptr mismatches new/delete and std::allocator for __shared_ptr_count spencer at starscale dot com ` (2 preceding siblings ...) 2013-10-08 13:38 ` redi at gcc dot gnu.org @ 2013-10-08 13:43 ` redi at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: redi at gcc dot gnu.org @ 2013-10-08 13:43 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58659 Jonathan Wakely <redi at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|ASSIGNED |RESOLVED Resolution|--- |FIXED --- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> --- I'm not going to backport this to the 4.7 branch, as it works fine in the default configuration. ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2013-10-08 13:43 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2013-10-07 21:16 [Bug libstdc++/58659] New: Construction of shared_ptr from unique_ptr mismatches new/delete and std::allocator for __shared_ptr_count spencer at starscale dot com 2013-10-07 21:36 ` [Bug libstdc++/58659] " redi at gcc dot gnu.org 2013-10-08 12:33 ` redi at gcc dot gnu.org 2013-10-08 13:38 ` redi at gcc dot gnu.org 2013-10-08 13:43 ` redi at gcc dot gnu.org
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