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From: "Nadav Har'El" <nyh@scylladb.com>
To: musl@lists.openwall.com
Cc: "Nadav Har'El" <nyh@scylladb.com>
Subject: Handling of L and ll prefixes different from glibc
Date: Wed, 14 Dec 2016 15:46:40 +0200	[thread overview]
Message-ID: <CANEVyjtv7+kqyDjyYiSv7yq7YLvvJo9Ti0PSGcjQ3dVMgjqF1w@mail.gmail.com> (raw)

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Hi,

Posix's printf manual suggests (see
http://pubs.opengroup.org/onlinepubs/9699919799/functions/fprintf.html)
that the "ll" format prefix should only be used for integer types, and "L"
should only be used for long double type. And it seems that indeed, this is
what Musl's printf() supports - the test program

    long double d = 123.456;
    printf("Lf: %Lf\n", d);
    printf("llf %llf\n", d);
    long long int i = 123456;
    printf("Ld: %Ld\n", i);
    printf("lld: %lld\n", i);

produces with Musl's printf just two lines of output:

    Lf: 123.456000
    lld: 123456

The two other printf()s (with %Ld and %llf) are silently dropped.

However, in glibc, it seems that "ll" and "L" are synonyms, and both work
for both integer and floating types. The above program produces with glibc
four lines of output:

    Lf: 123.456000
    llf 123.456000
    Ld: 123456
    lld: 123456

If Musl's intention is to be compatible with glibc, not Posix, I guess this
behavior should be fixed, and LL and ll should become synonyms, not
different flags?

Thanks,
Nadav.

--
Nadav Har'El
nyh@scylladb.com

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             reply	other threads:[~2016-12-14 13:46 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-12-14 13:46 Nadav Har'El [this message]
2016-12-14 16:13 ` Rich Felker
2016-12-14 17:17   ` Szabolcs Nagy
2016-12-14 22:37     ` A. Wilcox
2016-12-15  2:30       ` Rich Felker
2016-12-15  4:01         ` A. Wilcox
2016-12-15 11:30           ` Szabolcs Nagy

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