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From: "muecker at gwdg dot de" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/111808] [C23] constexpr with excess precision
Date: Tue, 17 Oct 2023 16:50:44 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D111808

--- Comment #6 from Martin Uecker <muecker at gwdg dot de> ---
Adding a note is a good idea, but it doesn't really solve the issue.  The
problem I see is that somebody developing on x86-64 does not get a warning =
that
the code is not strictly conforming and then it fails to build elsewhere.=
=20=20

Ideally, there is an algorithm which can decide whether the result is exact=
 in
all versions with same or higher precision or not.  Otherwise, computing it
with some higher precision and comparing the results would catch most probl=
ems
(but not all).=20

Alternatively, one could downgrade the error to warning. The code may then =
be
slightly wrong on i386 but at least the build does not fail.=