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From: "carlosgalvezp at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/107699] [12/13 Regression] False positive
 -Warray-bounds, non-existent offset reported by GCC
Date: Tue, 29 Nov 2022 13:46:18 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D107699

--- Comment #6 from Carlos Galvez <carlosgalvezp at gmail dot com> ---
A similar case in the real world would be this:

NumberSmallerThan3 getCount();

std::sort(data.begin(), data.begin() + static_cast<std::size_t>(getCount())=
);

The "NumberSmallerThan3" class holds and checks the invariant that "a numbe=
r is
smaller than 3". The compiler is not aware of that.

Other real-world situation is Eigen-like code, where for performance reasons
these checks can only be applied in debug mode, not release mode. We get
warnings in release mode due to this.=