compiler warnings when building on g++ 13.2 [C++, gcc 13.2, Debian testing]

Open rkuester opened this issue 2 years ago • 0 comments

Building on g++ 13.2.0, the current compiler in Debian testing, results in -Wstringop-overread warnings (logs below). This is reproducible with //tests:flatbuffers_test in today's master branch at 205285c3, and at least as far back as a66de58af (Aug 15, 2022).

% sdk bazel test //tests:flatbuffers_test

INFO: Analyzed target //tests:flatbuffers_test (47 packages loaded, 760 targets configured).
INFO: Found 1 test target...
INFO: From Compiling src/reflection.cpp [for tool]:
In file included from /usr/include/c++/13/string:51,
                 from bazel-out/k8-opt-exec-2B5CBBC6/bin/src/_virtual_includes/flatbuffers/flatbuffers/base.h:41,
                 from bazel-out/k8-opt-exec-2B5CBBC6/bin/src/_virtual_includes/flatbuffers/flatbuffers/array.h:20,
                 from bazel-out/k8-opt-exec-2B5CBBC6/bin/src/_virtual_includes/flatbuffers/flatbuffers/flatbuffers.h:22,
                 from bazel-out/k8-opt-exec-2B5CBBC6/bin/src/_virtual_includes/flatbuffers/flatbuffers/reflection_generated.h:7,
                 from bazel-out/k8-opt-exec-2B5CBBC6/bin/src/_virtual_includes/flatbuffers/flatbuffers/reflection.h:25,
                 from src/reflection.cpp:17:
In static member function 'static void std::__copy_move<false, false, std::random_access_iterator_tag>::__assign_one(_Tp*, _Up*) [with _Tp = unsigned char; _Up = const unsigned char]',
    inlined from 'static _Up* std::__copy_move<_IsMove, true, std::random_access_iterator_tag>::__copy_m(_Tp*, _Tp*, _Up*) [with _Tp = const unsigned char; _Up = unsigned char; bool _IsMove = false]' at /usr/include/c++/13/bits
/stl_algobase.h:440:20,
    inlined from '_OI std::__copy_move_a2(_II, _II, _OI) [with bool _IsMove = false; _II = const unsigned char*; _OI = unsigned char*]' at /usr/include/c++/13/bits/stl_algobase.h:506:30,
    inlined from '_OI std::__copy_move_a1(_II, _II, _OI) [with bool _IsMove = false; _II = const unsigned char*; _OI = unsigned char*]' at /usr/include/c++/13/bits/stl_algobase.h:533:42,
    inlined from '_OI std::__copy_move_a(_II, _II, _OI) [with bool _IsMove = false; _II = const unsigned char*; _OI = unsigned char*]' at /usr/include/c++/13/bits/stl_algobase.h:540:31,
    inlined from '_OI std::copy(_II, _II, _OI) [with _II = const unsigned char*; _OI = unsigned char*]' at /usr/include/c++/13/bits/stl_algobase.h:633:7,
    inlined from 'static _ForwardIterator std::__uninitialized_copy<true>::__uninit_copy(_InputIterator, _InputIterator, _ForwardIterator) [with _InputIterator = const unsigned char*; _ForwardIterator = unsigned char*]' at /usr
/include/c++/13/bits/stl_uninitialized.h:147:27,
    inlined from '_ForwardIterator std::uninitialized_copy(_InputIterator, _InputIterator, _ForwardIterator) [with _InputIterator = const unsigned char*; _ForwardIterator = unsigned char*]' at /usr/include/c++/13/bits/stl_uninitialized.h:185:15,
    inlined from '_ForwardIterator std::__uninitialized_copy_a(_InputIterator, _InputIterator, _ForwardIterator, allocator<_Tp>&) [with _InputIterator = const unsigned char*; _ForwardIterator = unsigned char*; _Tp = unsigned char]' at /usr/include/c++/13/bits/stl_uninitialized.h:373:37,
    inlined from 'void std::vector<_Tp, _Alloc>::_M_range_insert(iterator, _ForwardIterator, _ForwardIterator, std::forward_iterator_tag) [with _ForwardIterator = const unsigned char*; _Tp = unsigned char; _Alloc = std::allocator<unsigned char>]' at /usr/include/c++/13/bits/vector.tcc:814:38,
    inlined from 'std::vector<_Tp, _Alloc>::iterator std::vector<_Tp, _Alloc>::insert(const_iterator, _InputIterator, _InputIterator) [with _InputIterator = const unsigned char*; <template-parameter-2-2> = void; _Tp = unsigned char; _Alloc = std::allocator<unsigned char>]' at /usr/include/c++/13/bits/stl_vector.h:1483:19,
    inlined from 'const uint8_t* flatbuffers::AddFlatBuffer(std::vector<unsigned char>&, const uint8_t*, size_t)' at src/reflection.cpp:382:17:
/usr/include/c++/13/bits/stl_algobase.h:398:17: warning: writing 1 byte into a region of size 0 [-Wstringop-overflow=]
  398 |         { *__to = *__from; }
      |           ~~~~~~^~~~~~~~~
In file included from /usr/include/x86_64-linux-gnu/c++/13/bits/c++allocator.h:33,
                 from /usr/include/c++/13/bits/allocator.h:46,
                 from /usr/include/c++/13/string:43:
In member function '_Tp* std::__new_allocator<_Tp>::allocate(size_type, const void*) [with _Tp = unsigned char]',
    inlined from 'static _Tp* std::allocator_traits<std::allocator<_CharT> >::allocate(allocator_type&, size_type) [with _Tp = unsigned char]' at /usr/include/c++/13/bits/alloc_traits.h:482:28,
    inlined from 'std::_Vector_base<_Tp, _Alloc>::pointer std::_Vector_base<_Tp, _Alloc>::_M_allocate(std::size_t) [with _Tp = unsigned char; _Alloc = std::allocator<unsigned char>]' at /usr/include/c++/13/bits/stl_vector.h:378:33,
    inlined from 'std::_Vector_base<_Tp, _Alloc>::pointer std::_Vector_base<_Tp, _Alloc>::_M_allocate(std::size_t) [with _Tp = unsigned char; _Alloc = std::allocator<unsigned char>]' at /usr/include/c++/13/bits/stl_vector.h:375:7,
    inlined from 'void std::vector<_Tp, _Alloc>::_M_range_insert(iterator, _ForwardIterator, _ForwardIterator, std::forward_iterator_tag) [with _ForwardIterator = const unsigned char*; _Tp = unsigned char; _Alloc = std::allocator<unsigned char>]' at /usr/include/c++/13/bits/vector.tcc:805:40,
    inlined from 'std::vector<_Tp, _Alloc>::iterator std::vector<_Tp, _Alloc>::insert(const_iterator, _InputIterator, _InputIterator) [with _InputIterator = const unsigned char*; <template-parameter-2-2> = void; _Tp = unsigned char; _Alloc = std::allocator<unsigned char>]' at /usr/include/c++/13/bits/stl_vector.h:1483:19,
    inlined from 'const uint8_t* flatbuffers::AddFlatBuffer(std::vector<unsigned char>&, const uint8_t*, size_t)' at src/reflection.cpp:382:17:
/usr/include/c++/13/bits/new_allocator.h:147:55: note: at offset [-9223372036854775808, -4] into destination object of size [4, 9223372036854775807] allocated by 'operator new'
  147 |         return static_cast<_Tp*>(_GLIBCXX_OPERATOR_NEW(__n * sizeof(_Tp)));
      |                                                       ^
In static member function 'static _Up* std::__copy_move<_IsMove, true, std::random_access_iterator_tag>::__copy_m(_Tp*, _Tp*, _Up*) [with _Tp = const unsigned char; _Up = unsigned char; bool _IsMove = false]',
    inlined from '_OI std::__copy_move_a2(_II, _II, _OI) [with bool _IsMove = false; _II = const unsigned char*; _OI = unsigned char*]' at /usr/include/c++/13/bits/stl_algobase.h:506:30,
    inlined from '_OI std::__copy_move_a1(_II, _II, _OI) [with bool _IsMove = false; _II = const unsigned char*; _OI = unsigned char*]' at /usr/include/c++/13/bits/stl_algobase.h:533:42,
    inlined from '_OI std::__copy_move_a(_II, _II, _OI) [with bool _IsMove = false; _II = const unsigned char*; _OI = unsigned char*]' at /usr/include/c++/13/bits/stl_algobase.h:540:31,
    inlined from '_OI std::copy(_II, _II, _OI) [with _II = const unsigned char*; _OI = unsigned char*]' at /usr/include/c++/13/bits/stl_algobase.h:633:7,
    inlined from 'static _ForwardIterator std::__uninitialized_copy<true>::__uninit_copy(_InputIterator, _InputIterator, _ForwardIterator) [with _InputIterator = const unsigned char*; _ForwardIterator = unsigned char*]' at /usr
/include/c++/13/bits/stl_uninitialized.h:147:27,
    inlined from '_ForwardIterator std::uninitialized_copy(_InputIterator, _InputIterator, _ForwardIterator) [with _InputIterator = const unsigned char*; _ForwardIterator = unsigned char*]' at /usr/include/c++/13/bits/stl_uninitialized.h:185:15,
    inlined from '_ForwardIterator std::__uninitialized_copy_a(_InputIterator, _InputIterator, _ForwardIterator, allocator<_Tp>&) [with _InputIterator = const unsigned char*; _ForwardIterator = unsigned char*; _Tp = unsigned char]' at /usr/include/c++/13/bits/stl_uninitialized.h:373:37,
    inlined from 'void std::vector<_Tp, _Alloc>::_M_range_insert(iterator, _ForwardIterator, _ForwardIterator, std::forward_iterator_tag) [with _ForwardIterator = const unsigned char*; _Tp = unsigned char; _Alloc = std::allocator<unsigned char>]' at /usr/include/c++/13/bits/vector.tcc:814:38,
    inlined from 'std::vector<_Tp, _Alloc>::iterator std::vector<_Tp, _Alloc>::insert(const_iterator, _InputIterator, _InputIterator) [with _InputIterator = const unsigned char*; <template-parameter-2-2> = void; _Tp = unsigned char; _Alloc = std::allocator<unsigned char>]' at /usr/include/c++/13/bits/stl_vector.h:1483:19,
    inlined from 'const uint8_t* flatbuffers::AddFlatBuffer(std::vector<unsigned char>&, const uint8_t*, size_t)' at src/reflection.cpp:382:17:
/usr/include/c++/13/bits/stl_algobase.h:437:30: warning: 'void* __builtin_memcpy(void*, const void*, long unsigned int)' writing between 2 and 9223372036854775803 bytes into a region of size 0 overflows the destination [-Wstrin gop-overflow=]
  437 |             __builtin_memmove(__result, __first, sizeof(_Tp) * _Num);
      |             ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In member function '_Tp* std::__new_allocator<_Tp>::allocate(size_type, const void*) [with _Tp = unsigned char]',
    inlined from 'static _Tp* std::allocator_traits<std::allocator<_CharT> >::allocate(allocator_type&, size_type) [with _Tp = unsigned char]' at /usr/include/c++/13/bits/alloc_traits.h:482:28,
    inlined from 'std::_Vector_base<_Tp, _Alloc>::pointer std::_Vector_base<_Tp, _Alloc>::_M_allocate(std::size_t) [with _Tp = unsigned char; _Alloc = std::allocator<unsigned char>]' at /usr/include/c++/13/bits/stl_vector.h:378 :33,
    inlined from 'std::_Vector_base<_Tp, _Alloc>::pointer std::_Vector_base<_Tp, _Alloc>::_M_allocate(std::size_t) [with _Tp = unsigned char; _Alloc = std::allocator<unsigned char>]' at /usr/include/c++/13/bits/stl_vector.h:375 :7,
    inlined from 'void std::vector<_Tp, _Alloc>::_M_range_insert(iterator, _ForwardIterator, _ForwardIterator, std::forward_iterator_tag) [with _ForwardIterator = const unsigned char*; _Tp = unsigned char; _Alloc = std::allocator<unsigned char>]' at /usr/include/c++/13/bits/vector.tcc:805:40,
    inlined from 'std::vector<_Tp, _Alloc>::iterator std::vector<_Tp, _Alloc>::insert(const_iterator, _InputIterator, _InputIterator) [with _InputIterator = const unsigned char*; <template-parameter-2-2> = void; _Tp = unsigned char; _Alloc = std::allocator<unsigned char>]' at /usr/include/c++/13/bits/stl_vector.h:1483:19,
    inlined from 'const uint8_t* flatbuffers::AddFlatBuffer(std::vector<unsigned char>&, const uint8_t*, size_t)' at src/reflection.cpp:382:17:
/usr/include/c++/13/bits/new_allocator.h:147:55: note: at offset [-9223372036854775808, -4] into destination object of size [4, 9223372036854775807] allocated by 'operator new'
  147 |         return static_cast<_Tp*>(_GLIBCXX_OPERATOR_NEW(__n * sizeof(_Tp)));
      |                                                       ^
Target //tests:flatbuffers_test up-to-date:
  bazel-bin/tests/flatbuffers_test
INFO: Elapsed time: 21.754s, Critical Path: 8.78s
INFO: 197 processes: 142 internal, 55 linux-sandbox.
INFO: Build completed successfully, 197 total actions
//tests:flatbuffers_test                                                 PASSED in 0.0s

Executed 1 out of 1 test: 1 test passes.

Oct 13 '23 16:10 rkuester