https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96188
Egor Suvorov <egor_suvorov at mail dot ru> changed:
What |Removed |Added
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CC| |egor_suvorov at mail dot ru
--- Comment #4 from Egor Suvorov <egor_suvorov at mail dot ru> ---
A possibly related example (also available at Godbolt:
https://godbolt.org/z/P65dx1 )
At my Windows machine the following code
#include <vector>
int main() {
struct S { // Defining the structure inside main is important.
bool x = false; // Initialization is important.
};
std::vector<S> v(3); // Can also be 2, 3, and 4, but not 0, 1, 5, or 6.
v.emplace_back(S());
}
yields following when compiled with g++ -O2 -Wextra:
In member function 'void std::vector<_Tp, _Alloc>::emplace_back(_Args&& ...)
[with _Args = {main()::S}; _Tp = main()::S; _Alloc =
std::allocator<main()::S>]',
inlined from 'int main()' at a.cpp:7:19:
cc1plus.exe: warning: writing 1 byte into a region of size 0
[-Wstringop-overflow=]
In file included from
C:/Software/msys64/mingw64/include/c++/10.2.0/x86_64-w64-mingw32/bits/c++allocator.h:33,
from
C:/Software/msys64/mingw64/include/c++/10.2.0/bits/allocator.h:46,
from C:/Software/msys64/mingw64/include/c++/10.2.0/vector:64,
from a.cpp:1:
C:/Software/msys64/mingw64/include/c++/10.2.0/ext/new_allocator.h: In function
'int main()':
C:/Software/msys64/mingw64/include/c++/10.2.0/ext/new_allocator.h:115:41: note:
at offset 3 to an object with size 0 allocated by 'operator new' here
115 | return static_cast<_Tp*>(::operator new(__n * sizeof(_Tp)));
| ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~
My g++ version is
g++ (Rev6, Built by MSYS2 project) 10.2.0
Copyright (C) 2020 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
