Currently, a no-op lambda is used as the deleter for the temporary shared pointer helper in Sock::Wait. This is perfectly fine, but has a few style issues:
Fix all issues by just using an aliasing shared pointer, which points to this, but is otherwise empty (sits on the stack without any heap allocations).
The following sections might be updated with supplementary metadata relevant to reviewers and maintainers.
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| Type | Reviewers |
|---|---|
| ACK | hodlinator |
If your review is incorrectly listed, please copy-paste <!–meta-tag:bot-skip–> into the comment that the bot should ignore.
If someone wants to reproduce the GCC-16 warning on a fresh install of Fedora 43:
0dnf install -y git cmake pkgconfig boost-devel libevent-devel sqlite-devel capnproto capnproto-devel zeromq-devel ccache qt6-qttools-devel qt6-qtbase-devel qrencode-devel systemtap-sdt-devel python3-zmq libstdc++
1
2dnf -y copr enable jwakely/gcc-latest && dnf -y install gcc-latest
3
4git clone https://github.com/bitcoin/bitcoin.git --depth=1 ./b-c && cd b-c
5
6rm -rf ./bld/ && cmake -B bld -DCMAKE_C_COMPILER="/opt/gcc-latest/bin/gcc" -DCMAKE_CXX_COMPILER="/opt/gcc-latest/bin/g++;-static-libstdc++" --preset=dev-mode
7
8cmake --build ./bld -j $(nproc)
Will print:
0[ 13%] Building CXX object src/util/CMakeFiles/bitcoin_util.dir/sock.cpp.o
1In file included from /opt/gcc-latest/include/c++/16.0.1/bits/stl_iterator.h:78,
2 from /opt/gcc-latest/include/c++/16.0.1/bits/stl_algobase.h:66,
3 from /opt/gcc-latest/include/c++/16.0.1/bits/stl_algo.h:60,
4 from /opt/gcc-latest/include/c++/16.0.1/chrono:57,
5 from /b-c/src/util/time.h:9,
6 from /b-c/src/common/system.h:10,
7 from /b-c/src/util/sock.cpp:5:
8In function ‘constexpr void std::destroy_at(_Tp*) [with _Tp = mutex]’,
9 inlined from ‘constexpr void std::_Destroy(_Tp*) [with _Tp = mutex]’ at /opt/gcc-latest/include/c++/16.0.1/bits/stl_construct.h:164:22,
10 inlined from ‘static constexpr void std::allocator_traits<std::allocator<void> >::destroy(allocator_type&, _Up*) [with _Up = std::mutex]’ at /opt/gcc-latest/include/c++/16.0.1/bits/alloc_traits.h:819:17,
11 inlined from ‘void std::_Sp_counted_ptr_inplace<_Tp, _Alloc, _Lp>::_M_dispose() [with _Tp = std::mutex; _Alloc = std::allocator<void>; __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:675:35,
12 inlined from ‘void std::_Sp_counted_base<_Lp>::_M_release() [with __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:423:18,
13 inlined from ‘void std::_Sp_counted_base<_Lp>::_M_release() [with __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:392:5,
14 inlined from ‘std::__shared_count<_Lp>::~__shared_count() [with __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:1129:21,
15 inlined from ‘std::__shared_ptr<_Tp, _Lp>::~__shared_ptr() [with _Tp = const Sock; __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:1603:7,
16 inlined from ‘std::shared_ptr<const Sock>::~shared_ptr()’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr.h:175:11,
17 inlined from ‘virtual bool Sock::Wait(std::chrono::milliseconds, Event, Event*) const’ at /b-c/src/util/sock.cpp:157:1:
18/opt/gcc-latest/include/c++/16.0.1/bits/stl_construct.h:88:9: warning: array subscript ‘std::mutex[0]’ is partly outside array bounds of ‘unsigned char [24]’ [-Warray-bounds=]
19 88 | __location->~_Tp();
20 | ^~~~~~~~~~
21In file included from /opt/gcc-latest/include/c++/16.0.1/x86_64-pc-linux-gnu/bits/c++allocator.h:33,
22 from /opt/gcc-latest/include/c++/16.0.1/bits/allocator.h:46,
23 from /opt/gcc-latest/include/c++/16.0.1/string:46,
24 from /opt/gcc-latest/include/c++/16.0.1/bits/locale_classes.h:43,
25 from /opt/gcc-latest/include/c++/16.0.1/bits/ios_base.h:43,
26 from /opt/gcc-latest/include/c++/16.0.1/ios:46,
27 from /opt/gcc-latest/include/c++/16.0.1/istream:42,
28 from /opt/gcc-latest/include/c++/16.0.1/sstream:42,
29 from /opt/gcc-latest/include/c++/16.0.1/chrono:61:
30In member function ‘_Tp* std::__new_allocator<_Tp>::allocate(size_type, const void*) [with _Tp = std::_Sp_counted_deleter<const Sock*, Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>, std::allocator<void>, __gnu_cxx::_S_atomic>]’,
31 inlined from ‘constexpr _Tp* std::allocator< <template-parameter-1-1> >::allocate(std::size_t) [with _Tp = std::_Sp_counted_deleter<const Sock*, Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>, std::allocator<void>, __gnu_cxx::_S_atomic>]’ at /opt/gcc-latest/include/c++/16.0.1/bits/allocator.h:203:40,
32 inlined from ‘static constexpr _Tp* std::allocator_traits<std::allocator<_CharT> >::allocate(allocator_type&, size_type) [with _Tp = std::_Sp_counted_deleter<const Sock*, Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>, std::allocator<void>, __gnu_cxx::_S_atomic>]’ at /opt/gcc-latest/include/c++/16.0.1/bits/alloc_traits.h:614:28,
33 inlined from ‘std::__allocated_ptr<_Alloc> std::__allocate_guarded(_Alloc&) [with _Alloc = allocator<_Sp_counted_deleter<const Sock*, Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>, allocator<void>, __gnu_cxx::_S_atomic> >]’ at /opt/gcc-latest/include/c++/16.0.1/bits/allocated_ptr.h:103:69,
34 inlined from ‘std::__shared_count<_Lp>::__shared_count(_Ptr, _Deleter, _Alloc) [with _Ptr = const Sock*; _Deleter = Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>; _Alloc = std::allocator<void>; <template-parameter-2-4> = void; __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:1007:13,
35 inlined from ‘std::__shared_count<_Lp>::__shared_count(_Ptr, _Deleter) [with _Ptr = const Sock*; _Deleter = Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>; <template-parameter-2-3> = void; __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:996:57,
36 inlined from ‘std::__shared_ptr<_Tp, _Lp>::__shared_ptr(_Yp*, _Deleter) [with _Yp = const Sock; _Deleter = Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>; <template-parameter-2-3> = void; _Tp = const Sock; __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:1557:17,
37 inlined from ‘std::shared_ptr<_Tp>::shared_ptr(_Yp*, _Deleter) [with _Yp = const Sock; _Deleter = Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>; <template-parameter-2-3> = void; _Tp = const Sock]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr.h:231:48,
38 inlined from ‘virtual bool Sock::Wait(std::chrono::milliseconds, Event, Event*) const’ at /b-c/src/util/sock.cpp:144:64:
39/opt/gcc-latest/include/c++/16.0.1/bits/new_allocator.h:151:73: note: at offset 16 into object of size 24 allocated by ‘operator new’
40 151 | return static_cast<_Tp*>(_GLIBCXX_OPERATOR_NEW(__n * sizeof(_Tp)));
41 | ^
42In file included from /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr.h:53,
43 from /opt/gcc-latest/include/c++/16.0.1/chrono:64:
44In destructor ‘std::_Sp_counted_ptr_inplace<_Tp, _Alloc, _Lp>::~_Sp_counted_ptr_inplace() [with _Tp = std::mutex; _Alloc = std::allocator<void>; __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’,
45 inlined from ‘std::_Sp_counted_ptr_inplace<_Tp, _Alloc, _Lp>::~_Sp_counted_ptr_inplace() [with _Tp = std::mutex; _Alloc = std::allocator<void>; __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:670:45,
46 inlined from ‘void std::_Sp_counted_base<_Lp>::_M_destroy() [with __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:143:9,
47 inlined from ‘void std::_Sp_counted_base<_Lp>::_M_release() [with __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:424:18,
48 inlined from ‘void std::_Sp_counted_base<_Lp>::_M_release() [with __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:392:5,
49 inlined from ‘std::__shared_count<_Lp>::~__shared_count() [with __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:1129:21,
50 inlined from ‘std::__shared_ptr<_Tp, _Lp>::~__shared_ptr() [with _Tp = const Sock; __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:1603:7,
51 inlined from ‘std::shared_ptr<const Sock>::~shared_ptr()’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr.h:175:11,
52 inlined from ‘virtual bool Sock::Wait(std::chrono::milliseconds, Event, Event*) const’ at /b-c/src/util/sock.cpp:157:1:
53/opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:670:45: warning: array subscript ‘std::_Sp_counted_ptr_inplace<std::mutex, std::allocator<void>, __gnu_cxx::_S_atomic>[0]’ is partly outside array bounds of ‘unsigned char [24]’ [-Warray-bounds=]
54 670 | ~_Sp_counted_ptr_inplace() noexcept { }
55 | ^
56In member function ‘_Tp* std::__new_allocator<_Tp>::allocate(size_type, const void*) [with _Tp = std::_Sp_counted_deleter<const Sock*, Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>, std::allocator<void>, __gnu_cxx::_S_atomic>]’,
57 inlined from ‘constexpr _Tp* std::allocator< <template-parameter-1-1> >::allocate(std::size_t) [with _Tp = std::_Sp_counted_deleter<const Sock*, Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>, std::allocator<void>, __gnu_cxx::_S_atomic>]’ at /opt/gcc-latest/include/c++/16.0.1/bits/allocator.h:203:40,
58 inlined from ‘static constexpr _Tp* std::allocator_traits<std::allocator<_CharT> >::allocate(allocator_type&, size_type) [with _Tp = std::_Sp_counted_deleter<const Sock*, Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>, std::allocator<void>, __gnu_cxx::_S_atomic>]’ at /opt/gcc-latest/include/c++/16.0.1/bits/alloc_traits.h:614:28,
59 inlined from ‘std::__allocated_ptr<_Alloc> std::__allocate_guarded(_Alloc&) [with _Alloc = allocator<_Sp_counted_deleter<const Sock*, Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>, allocator<void>, __gnu_cxx::_S_atomic> >]’ at /opt/gcc-latest/include/c++/16.0.1/bits/allocated_ptr.h:103:69,
60 inlined from ‘std::__shared_count<_Lp>::__shared_count(_Ptr, _Deleter, _Alloc) [with _Ptr = const Sock*; _Deleter = Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>; _Alloc = std::allocator<void>; <template-parameter-2-4> = void; __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:1007:13,
61 inlined from ‘std::__shared_count<_Lp>::__shared_count(_Ptr, _Deleter) [with _Ptr = const Sock*; _Deleter = Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>; <template-parameter-2-3> = void; __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:996:57,
62 inlined from ‘std::__shared_ptr<_Tp, _Lp>::__shared_ptr(_Yp*, _Deleter) [with _Yp = const Sock; _Deleter = Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>; <template-parameter-2-3> = void; _Tp = const Sock; __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:1557:17,
63 inlined from ‘std::shared_ptr<_Tp>::shared_ptr(_Yp*, _Deleter) [with _Yp = const Sock; _Deleter = Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>; <template-parameter-2-3> = void; _Tp = const Sock]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr.h:231:48,
64 inlined from ‘virtual bool Sock::Wait(std::chrono::milliseconds, Event, Event*) const’ at /b-c/src/util/sock.cpp:144:64:
65/opt/gcc-latest/include/c++/16.0.1/bits/new_allocator.h:151:73: note: object of size 24 allocated by ‘operator new’
66 151 | return static_cast<_Tp*>(_GLIBCXX_OPERATOR_NEW(__n * sizeof(_Tp)));
67 | ^
68In destructor ‘std::_Sp_counted_ptr_inplace<_Tp, _Alloc, _Lp>::~_Sp_counted_ptr_inplace() [with _Tp = std::mutex; _Alloc = std::allocator<void>; __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’,
69 inlined from ‘void std::_Sp_counted_ptr_inplace<_Tp, _Alloc, _Lp>::_M_destroy() [with _Tp = std::mutex; _Alloc = std::allocator<void>; __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:684:32,
70 inlined from ‘void std::_Sp_counted_base<_Lp>::_M_release() [with __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:424:18,
71 inlined from ‘void std::_Sp_counted_base<_Lp>::_M_release() [with __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:392:5,
72 inlined from ‘std::__shared_count<_Lp>::~__shared_count() [with __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:1129:21,
73 inlined from ‘std::__shared_ptr<_Tp, _Lp>::~__shared_ptr() [with _Tp = const Sock; __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:1603:7,
74 inlined from ‘std::shared_ptr<const Sock>::~shared_ptr()’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr.h:175:11,
75 inlined from ‘virtual bool Sock::Wait(std::chrono::milliseconds, Event, Event*) const’ at /b-c/src/util/sock.cpp:157:1:
76/opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:670:45: warning: array subscript ‘std::_Sp_counted_ptr_inplace<std::mutex, std::allocator<void>, __gnu_cxx::_S_atomic>[0]’ is partly outside array bounds of ‘unsigned char [24]’ [-Warray-bounds=]
77 670 | ~_Sp_counted_ptr_inplace() noexcept { }
78 | ^
79In member function ‘_Tp* std::__new_allocator<_Tp>::allocate(size_type, const void*) [with _Tp = std::_Sp_counted_deleter<const Sock*, Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>, std::allocator<void>, __gnu_cxx::_S_atomic>]’,
80 inlined from ‘constexpr _Tp* std::allocator< <template-parameter-1-1> >::allocate(std::size_t) [with _Tp = std::_Sp_counted_deleter<const Sock*, Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>, std::allocator<void>, __gnu_cxx::_S_atomic>]’ at /opt/gcc-latest/include/c++/16.0.1/bits/allocator.h:203:40,
81 inlined from ‘static constexpr _Tp* std::allocator_traits<std::allocator<_CharT> >::allocate(allocator_type&, size_type) [with _Tp = std::_Sp_counted_deleter<const Sock*, Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>, std::allocator<void>, __gnu_cxx::_S_atomic>]’ at /opt/gcc-latest/include/c++/16.0.1/bits/alloc_traits.h:614:28,
82 inlined from ‘std::__allocated_ptr<_Alloc> std::__allocate_guarded(_Alloc&) [with _Alloc = allocator<_Sp_counted_deleter<const Sock*, Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>, allocator<void>, __gnu_cxx::_S_atomic> >]’ at /opt/gcc-latest/include/c++/16.0.1/bits/allocated_ptr.h:103:69,
83 inlined from ‘std::__shared_count<_Lp>::__shared_count(_Ptr, _Deleter, _Alloc) [with _Ptr = const Sock*; _Deleter = Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>; _Alloc = std::allocator<void>; <template-parameter-2-4> = void; __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:1007:13,
84 inlined from ‘std::__shared_count<_Lp>::__shared_count(_Ptr, _Deleter) [with _Ptr = const Sock*; _Deleter = Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>; <template-parameter-2-3> = void; __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:996:57,
85 inlined from ‘std::__shared_ptr<_Tp, _Lp>::__shared_ptr(_Yp*, _Deleter) [with _Yp = const Sock; _Deleter = Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>; <template-parameter-2-3> = void; _Tp = const Sock; __gnu_cxx::_Lock_policy _Lp = __gnu_cxx::_S_atomic]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr_base.h:1557:17,
86 inlined from ‘std::shared_ptr<_Tp>::shared_ptr(_Yp*, _Deleter) [with _Yp = const Sock; _Deleter = Sock::Wait(std::chrono::milliseconds, Event, Event*) const::<lambda(const Sock*)>; <template-parameter-2-3> = void; _Tp = const Sock]’ at /opt/gcc-latest/include/c++/16.0.1/bits/shared_ptr.h:231:48,
87 inlined from ‘virtual bool Sock::Wait(std::chrono::milliseconds, Event, Event*) const’ at /b-c/src/util/sock.cpp:144:64:
88/opt/gcc-latest/include/c++/16.0.1/bits/new_allocator.h:151:73: note: object of size 24 allocated by ‘operator new’
89 151 | return static_cast<_Tp*>(_GLIBCXX_OPERATOR_NEW(__n * sizeof(_Tp)));
90 | ^
91[ 13%] Linking CXX static library ../../lib/libbitcoin_util.a
(This pull fixes it)
ACK faa016af542763492a63de8cc972f8f4b52a58cd
Uses shared_ptr’s aliasing ctor1 to have the local shared variable to take over the any heap-allocated refcount, which can even be nullptr for default-initialized shared_ptrs. (Example usage of l-value overload of aliasing ctor: https://stackoverflow.com/a/27109774).
(The custom deleter on master would need to live on the heap to outlive short-lived shared_ptr instances. The refcount and custom deleter would probably be allocated together, but specializations of shared_ptr without the custom deleter could have a smaller allocation).
Edit: Slight correction after #34471 (comment)
Uses
shared_ptr’s aliasing ctor to have the localsharedvariable to take over the heap-allocated refcount (https://en.cppreference.com/w/cpp/memory/shared_ptr/shared_ptr.html) . (Example usage of l-value overload of aliasing ctor: https://stackoverflow.com/a/27109774).
Just for reference, and not important, but in the specific case of the code in this pull request, there is no need for any heap-allocation at all. It is just two nullptr on the stack (for the empty ptr), and still two pointers on the stack after passing to the aliasing ctor. At least in libcxx: https://github.com/llvm/llvm-project/blob/2f0400c1a15b7b1ff401cc12902f7de5856cf1f7/libcxx/include/__memory/shared_ptr.h#L321-L328 and https://github.com/llvm/llvm-project/blob/2f0400c1a15b7b1ff401cc12902f7de5856cf1f7/libcxx/include/__memory/shared_ptr.h#L426-L443
Labels
Refactoring