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From: "oplata.kes1 at mail dot ru" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/111747] Problem with large float list initialization
Date: Tue, 10 Oct 2023 19:52:22 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D111747

--- Comment #2 from oplata.kes1 at mail dot ru ---
(In reply to Andrew Pinski from comment #1)
>=20
> 32bit floating point has the following characteristics:
> Sign bit: 1 bit
> Exponent width: 8 bits
> Significand precision: 24 bits (23 explicitly stored)
>=20
>=20
> 50000000 is 0x2faf080 which is more than 24bits in precision which means =
it
> cannot be represented exactly and when you start to add 1 to something wh=
ich
> is greater than 0xfffff0 (which is what 1.67772e+07 is), the value stays =
the
> same and you start to lose precision.

Thank you very much!=