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From: "michael.ragazzon at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/110498] Spurious warnings stringop-overflow
 and array-bounds copying data as bytes into vector::reserve
Date: Tue, 02 Apr 2024 20:20:49 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D110498

Michael Ragazzon <michael.ragazzon at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |michael.ragazzon at gmail =
dot com

--- Comment #1 from Michael Ragazzon <michael.ragazzon at gmail dot com> ---
I seem to also have encountered this issue while using `std::vector<bool>`.
Here is a relatively small reproducer.

Compile with: -O3 -std=3Dc++17 -Wall -Werror

---

#include <stdio.h>
#include <vector>

class Testing {
public:
        Testing();

private:
        std::vector<bool> elements;
};

Testing::Testing()
{
        // Warning emitted when set to any number in the range [1,64].
        constexpr size_t reserve_size =3D 30;

        elements.reserve(reserve_size);
        elements.push_back(0);
}

int main() {
    Testing testing;
}

---

https://godbolt.org/z/eG66sjsPq

This issue seems to have started with GCC 13.1, and exists also on current
trunk (tested on Compiler Explorer).=