{"id":2233366,"url":"http://patchwork.ozlabs.org/api/1.1/patches/2233366/?format=json","web_url":"http://patchwork.ozlabs.org/project/gcc/patch/20260506085339.325517-2-jwakely@redhat.com/","project":{"id":17,"url":"http://patchwork.ozlabs.org/api/1.1/projects/17/?format=json","name":"GNU Compiler Collection","link_name":"gcc","list_id":"gcc-patches.gcc.gnu.org","list_email":"gcc-patches@gcc.gnu.org","web_url":null,"scm_url":null,"webscm_url":null},"msgid":"<20260506085339.325517-2-jwakely@redhat.com>","date":"2026-05-06T08:48:05","name":"[v2,2/3] libstdc++: Simplify std::shared_ptr internals","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"2e1d793df25dfac4c324243cac326a8460341089","submitter":{"id":48004,"url":"http://patchwork.ozlabs.org/api/1.1/people/48004/?format=json","name":"Jonathan Wakely","email":"jwakely@redhat.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/gcc/patch/20260506085339.325517-2-jwakely@redhat.com/mbox/","series":[{"id":502950,"url":"http://patchwork.ozlabs.org/api/1.1/series/502950/?format=json","web_url":"http://patchwork.ozlabs.org/project/gcc/list/?series=502950","date":"2026-05-06T08:48:05","name":"[v2,1/3] libstdc++: Replace uses of EBO with [[no_unique_address]]","version":2,"mbox":"http://patchwork.ozlabs.org/series/502950/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2233366/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2233366/checks/","tags":{},"headers":{"Return-Path":"","X-Original-To":["incoming@patchwork.ozlabs.org","gcc-patches@gcc.gnu.org"],"Delivered-To":["patchwork-incoming@legolas.ozlabs.org","gcc-patches@gcc.gnu.org"],"Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (1024-bit key;\n unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256\n header.s=mimecast20190719 header.b=DeP3fKdO;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=gcc.gnu.org\n (client-ip=38.145.34.32; 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}\n-\t_Alloc& _M_alloc() noexcept { return _M_a._M_obj; }\n-\n-\t_Ptr _M_ptr;\n- };\n-\n public:\n using __allocator_type = __alloc_rebind<_Alloc, _Sp_counted_deleter>;\n \n // __d(__p) must not throw.\n _Sp_counted_deleter(_Ptr __p, _Deleter __d) noexcept\n- : _M_impl(__p, std::move(__d), _Alloc()) { }\n+ : _M_del{std::move(__d)}, _M_alloc{}, _M_ptr(__p) { }\n \n // __d(__p) must not throw.\n _Sp_counted_deleter(_Ptr __p, _Deleter __d, const _Alloc& __a) noexcept\n- : _M_impl(__p, std::move(__d), __a) { }\n+ : _M_del{std::move(__d)}, _M_alloc{__a}, _M_ptr(__p) { }\n \n #pragma GCC diagnostic push // PR tree-optimization/122197\n #pragma GCC diagnostic ignored \"-Wfree-nonheap-object\"\n@@ -582,12 +566,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION\n \n virtual void\n _M_dispose() noexcept\n- { _M_impl._M_del()(_M_impl._M_ptr); }\n+ { _M_del._M_obj(_M_ptr); }\n \n virtual void\n _M_destroy() noexcept\n {\n-\t__allocator_type __a(_M_impl._M_alloc());\n+\t__allocator_type __a(_M_alloc._M_obj);\n \t__allocated_ptr<__allocator_type> __guard_ptr{ __a, this };\n \tthis->~_Sp_counted_deleter();\n }\n@@ -598,19 +582,20 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION\n #if __cpp_rtti\n \t// _GLIBCXX_RESOLVE_LIB_DEFECTS\n \t// 2400. shared_ptr's get_deleter() should use addressof()\n- return __ti == typeid(_Deleter)\n-\t ? std::__addressof(_M_impl._M_del())\n-\t : nullptr;\n-#else\n- return nullptr;\n+\tif (__ti == typeid(_Deleter))\n+\t return std::__addressof(_M_del._M_obj);\n #endif\n+\treturn nullptr;\n }\n \n private:\n #ifdef __glibcxx_out_ptr\n template friend class out_ptr_t;\n #endif\n- _Impl _M_impl;\n+\n+ [[__no_unique_address__]] _Sp_ebo_helper<_Deleter> _M_del;\n+ [[__no_unique_address__]] _Sp_ebo_helper<_Alloc> _M_alloc;\n+ _Ptr _M_ptr;\n };\n \n // helpers for make_shared / allocate_shared\n@@ -640,25 +625,13 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION\n template\n class _Sp_counted_ptr_inplace final : public _Sp_counted_base<_Lp>\n {\n- class _Impl\n- {\n-\t[[__no_unique_address__]] _Sp_ebo_helper<_Alloc> _M_a;\n-\n- public:\n-\texplicit _Impl(_Alloc __a) noexcept : _M_a{std::move(__a)} { }\n-\n-\t_Alloc& _M_alloc() noexcept { return _M_a._M_obj; }\n-\n-\t__gnu_cxx::__aligned_buffer<__remove_cv_t<_Tp>> _M_storage;\n- };\n-\n public:\n using __allocator_type = __alloc_rebind<_Alloc, _Sp_counted_ptr_inplace>;\n \n // Alloc parameter is not a reference so doesn't alias anything in __args\n template\n \t_Sp_counted_ptr_inplace(_Alloc __a, _Args&&... __args)\n-\t: _M_impl(__a)\n+\t: _M_alloc{__a}\n \t{\n \t // _GLIBCXX_RESOLVE_LIB_DEFECTS\n \t // 2070. allocate_shared should use allocator_traits::construct\n@@ -674,14 +647,14 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION\n virtual void\n _M_dispose() noexcept\n {\n-\tallocator_traits<_Alloc>::destroy(_M_impl._M_alloc(), _M_ptr());\n+\tallocator_traits<_Alloc>::destroy(_M_alloc._M_obj, _M_ptr());\n }\n \n // Override because the allocator needs to know the dynamic type\n virtual void\n _M_destroy() noexcept\n {\n-\t__allocator_type __a(_M_impl._M_alloc());\n+\t__allocator_type __a(_M_alloc._M_obj);\n \t__allocated_ptr<__allocator_type> __guard_ptr{ __a, this };\n \tthis->~_Sp_counted_ptr_inplace();\n }\n@@ -711,9 +684,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION\n }\n \n __remove_cv_t<_Tp>*\n- _M_ptr() noexcept { return _M_impl._M_storage._M_ptr(); }\n+ _M_ptr() noexcept { return _M_storage._M_ptr(); }\n \n- _Impl _M_impl;\n+ [[__no_unique_address__]] _Sp_ebo_helper<_Alloc> _M_alloc;\n+ __gnu_cxx::__aligned_buffer<__remove_cv_t<_Tp>> _M_storage;\n };\n \n #ifdef __glibcxx_smart_ptr_for_overwrite // C++ >= 20 && HOSTED\n","prefixes":["v2","2/3"]}