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From: "vincent-gcc at vinc17 dot net" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/114746] With FLT_EVAL_METHOD = 2, -fexcess-precision=fast reduces the precision of floating-point constants and floating-point constant expressions
Date: Wed, 01 May 2024 23:37:16 +0000	[thread overview]
Message-ID: <bug-114746-4-7yGS5Ixuvo@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-114746-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114746

--- Comment #7 from Vincent Lefèvre <vincent-gcc at vinc17 dot net> ---
BTW, in /usr/include/math.h from the GNU libc 2.37:

# define M_PI           3.14159265358979323846  /* pi */

i.e. M_PI is defined with 21 digits in base 10, which corresponds to about 70
digits in base 2, thus with the apparent intent to be accurate in extended
precision (64 digits).

      parent reply	other threads:[~2024-05-01 23:37 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-04-16 17:51 [Bug c/114746] New: With FLT_EVAL_METHOD = 2, -fexcess-precision=fast reduces the precision of floating-point constants vincent-gcc at vinc17 dot net
2024-04-17 23:18 ` [Bug c/114746] " vincent-gcc at vinc17 dot net
2024-04-17 23:23 ` [Bug c/114746] With FLT_EVAL_METHOD = 2, -fexcess-precision=fast reduces the precision of floating-point constants and floating-point constant expressions vincent-gcc at vinc17 dot net
2024-04-19 16:50 ` jsm28 at gcc dot gnu.org
2024-04-22  9:23 ` vincent-gcc at vinc17 dot net
2024-04-22 12:35 ` jakub at gcc dot gnu.org
2024-04-22 21:50 ` vincent-gcc at vinc17 dot net
2024-05-01 23:37 ` vincent-gcc at vinc17 dot net [this message]

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