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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/110145] 20_util/to_chars/double.cc fails for -m32 -fexcess-precision=standard
Date: Wed, 07 Jun 2023 09:12:29 +0000 [thread overview]
Message-ID: <bug-110145-4-686oI2Muu4@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-110145-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110145
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |jsm28 at gcc dot gnu.org
--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Actually, even simple
double a = 1e126;
int
main ()
{
__builtin_printf ("%.13a\n", a);
}
behaves differently in C between -m64 and -m32 -fexcess-precision=standard.
-m64 gives
0x1.7a2ecc414a03fp+418
while -m32 -fexcess-precision=standard gives
0x1.7a2ecc414a040p+418
Now, 1e126L is 0xb.d176620a501fc0000000000000p+415, which is that
0x1.7a2ecc414a03fp+418
exactly. So wonder why we try to round that up.
next prev parent reply other threads:[~2023-06-07 9:12 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-06 16:20 [Bug libstdc++/110145] New: " redi at gcc dot gnu.org
2023-06-06 16:34 ` [Bug libstdc++/110145] " jakub at gcc dot gnu.org
2023-06-06 16:40 ` redi at gcc dot gnu.org
2023-06-06 17:06 ` jakub at gcc dot gnu.org
2023-06-07 9:12 ` jakub at gcc dot gnu.org [this message]
2023-06-07 9:42 ` jakub at gcc dot gnu.org
2023-06-07 9:50 ` jakub at gcc dot gnu.org
2023-06-07 13:49 ` jakub at gcc dot gnu.org
2023-06-07 17:28 ` cvs-commit at gcc dot gnu.org
2023-06-09 12:21 ` redi at gcc dot gnu.org
2023-07-27 9:26 ` rguenth at gcc dot gnu.org
2024-05-21 9:15 ` jakub at gcc dot gnu.org
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