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From: "marxin at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug tree-optimization/104964] Wrong *** buffer overflow detected
 ***: terminated - acl
Date: Tue, 22 Mar 2022 08:20:15 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D104964

--- Comment #6 from Martin Li=C5=A1ka <marxin at gcc dot gnu.org> ---
I've got something similar that can be seen in libqt5core library:

QByteArray qt_readlink(const char *path)
{
#ifndef PATH_MAX
    // suitably large value that won't consume too much memory
#  define PATH_MAX  1024*1024
#endif

    QByteArray buf(256, Qt::Uninitialized);

    ssize_t len =3D ::readlink(path, buf.data(), buf.size());

...

where they use something like:

struct QArrayData
{
...
    void *data()
    {
        return reinterpret_cast<char *>(this) + offset;
    }

Can't easily reproduce a small test can thought.=