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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/89979] subtract_with_carry_engine incorrect carry flag
Date: Sun, 22 Aug 2021 21:46:46 +0000	[thread overview]
Message-ID: <bug-89979-4-Av5B0y0a3r@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-89979-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89979

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
LLVM's libc++ does not go into the 0 loop but still does not do a good job:
4294967295 0 0 0 0 0 0 1
0 0 0 0 0 0 0 1
0 0 0 0 0 0 4294967295 1
0 0 0 0 0 4294967295 4294967295 1
0 0 0 0 4294967295 4294967295 4294967295 1
0 0 0 4294967295 4294967295 4294967295 4294967294 0
0 0 4294967295 4294967295 4294967295 4294967294 4294967295 0
0 4294967295 4294967295 4294967295 4294967294 4294967295 4294967295 0
4294967295 4294967295 4294967295 4294967294 4294967295 4294967295 4294967294 0
4294967295 4294967295 4294967294 4294967295 4294967295 4294967294 0 0
4294967295 4294967294 4294967295 4294967295 4294967294 0 0 0
4294967294 4294967295 4294967295 4294967294 0 0 4294967295 1


While libstdc++ does seems to get into a loop:
4294967295 0 0 0 0 0 0 1 0
0 0 0 0 0 0 0 0 1
0 0 0 0 0 0 0 0 2
0 0 0 0 0 0 0 0 3
0 0 0 0 0 0 0 0 4
0 0 0 0 0 0 0 0 5
0 0 0 0 0 0 0 0 6
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 1
0 0 0 0 0 0 0 0 2
0 0 0 0 0 0 0 0 3
0 0 0 0 0 0 0 0 4

       reply	other threads:[~2021-08-22 21:46 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <bug-89979-4@http.gcc.gnu.org/bugzilla/>
2021-08-22 21:46 ` pinskia at gcc dot gnu.org [this message]
2021-08-31  9:39 ` gcc@christoph-conrads.name

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