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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/113679] long long minus double with gcc -m32 produces different results than other compilers or gcc -m64
Date: Wed, 31 Jan 2024 15:53:22 +0000	[thread overview]
Message-ID: <bug-113679-4-ygEkVBarZx@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-113679-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113679

--- Comment #11 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Anyway, seems clang is buggy:
clang -O2 -m32 -mno-sse -mfpmath=387 -fexcess-precision=standard
#include <float.h>

int
main ()
{
#if FLT_EVAL_METHOD == 2 && LDBL_MANT_DIG == 64 && DBL_MANT_DIG == 53
  if ((double) 191.18831051580915 == 191.18831051580915)
    __builtin_abort ();
#endif
}
should always succeed, because if FLT_EVAL_METHOD is 2, it ought to be
evaluated
as (long double) (double) 191.18831051580915L == 191.18831051580915L and
(double) 191.18831051580915L is 0x1.7e606a3c65c95p+7 while
191.18831051580915L is 0x1.7e606a3c65c9503ap+7L, so they aren't equal.

  parent reply	other threads:[~2024-01-31 15:53 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-01-31  8:40 [Bug c/113679] New: " dilyan.palauzov at aegee dot org
2024-01-31  8:44 ` [Bug target/113679] " pinskia at gcc dot gnu.org
2024-01-31  8:45 ` dilyan.palauzov at aegee dot org
2024-01-31  8:52 ` pinskia at gcc dot gnu.org
2024-01-31  8:53 ` jakub at gcc dot gnu.org
2024-01-31  9:58 ` dilyan.palauzov at aegee dot org
2024-01-31 10:02 ` pinskia at gcc dot gnu.org
2024-01-31 10:26 ` jakub at gcc dot gnu.org
2024-01-31 14:32 ` dilyan.palauzov at aegee dot org
2024-01-31 14:35 ` jakub at gcc dot gnu.org
2024-01-31 14:38 ` jakub at gcc dot gnu.org
2024-01-31 15:53 ` jakub at gcc dot gnu.org [this message]
2024-02-07  5:55 ` egallager at gcc dot gnu.org
2024-02-10 14:32 ` dilyan.palauzov at aegee dot org

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