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From: Morten Welinder <mwelinder@gmail.com>
To: musl@lists.openwall.com
Subject: printf issues
Date: Fri, 4 Apr 2014 09:32:18 -0400	[thread overview]
Message-ID: <CANv4PNn7=o6bNb5YzhiH39gTfiNFfj8G2P2FxH7XcYF3gx9VxA@mail.gmail.com> (raw)

I am seeing differences in how printf("%.200Lg",val) works between musl code
and glibc.

Here are some samples.  The top line is how musl prints, the bottom is glibc.

-65878995336522048.000000000
-65878995336522048

1954675876964773.500000000
1954675876964773.5

3953605802361882.000000000
3953605802361882


Unrelatedly, from function fmt_fp:

#define CONCAT2(x,y) x ## y
#define CONCAT(x,y) CONCAT2(x,y)
[...]
            long double round = CONCAT(0x1p,LDBL_MANT_DIG);

That code is cute as a Hello Kitty door knocker, but really?  Let's hope nobody
gets the urge to define LDBL_MANT_DIG as 0100 or (80-16) or some such.
The first case will still compile, but get the wrong result.

Morten


             reply	other threads:[~2014-04-04 13:32 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-04-04 13:32 Morten Welinder [this message]
2014-04-04 14:12 ` Rich Felker
2014-04-04 14:15 ` Szabolcs Nagy
2014-04-04 14:35   ` Morten Welinder
2014-04-04 14:56     ` Szabolcs Nagy
2014-04-04 15:07     ` Rich Felker
2014-04-04 17:42       ` Morten Welinder
2014-04-04 18:54         ` Szabolcs Nagy
2014-04-04 20:01           ` Morten Welinder
2014-04-04 20:22             ` Morten Welinder
2014-04-04 21:08               ` Rich Felker
2014-04-04 22:50                 ` Morten Welinder
2014-04-05  0:01                   ` Morten Welinder
2014-04-05  1:41                     ` Rich Felker
2014-04-07  7:29                     ` Rich Felker
2014-04-07 13:40                       ` Morten Welinder
2014-04-07 14:13                         ` Morten Welinder
2014-04-07 15:36                           ` Szabolcs Nagy
2014-04-07 18:04                             ` Rich Felker
2014-04-04 20:54             ` Szabolcs Nagy
2014-04-04 21:02             ` Rich Felker
2014-04-05  2:08               ` Morten Welinder
2014-04-05  2:50                 ` Rich Felker
2014-04-06 23:07                   ` Szabolcs Nagy
2014-04-04 21:00           ` Rich Felker
2014-04-04 21:10             ` Szabolcs Nagy
2014-04-04 20:58         ` Rich Felker

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