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From: "vincent-gcc at vinc17 dot net" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug middle-end/102930] equal values appear to be different due to
 missing correct rounding in libc
Date: Mon, 25 Oct 2021 13:51:47 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D102930

--- Comment #1 from Vincent Lef=C3=A8vre <vincent-gcc at vinc17 dot net> ---
I forgot some information: Debian unstable currently has libc6 2.32-4, where
IBM's code for correct rounding was disabled some time ago. This bug might =
be
unreproducible with other glibc versions (or other C libraries[*]). A chang=
e of
the tested function and argument should make the same kind of issue appear =
on
other platforms.

However, I've just done a test on a Debian 10 (buster) machine (libc6 2.28-=
10),
and the bug is reproducible on this machine.

[*] A result may be correctly rounded by chance; this completely depends on=
 the
implementation.=