[FFmpeg-devel] regression - mpeg2 interlace/topfield flags not set anymore

Michel Bardiaux mbardiaux
Mon Jan 28 11:06:51 CET 2008

Diego Biurrun a ?crit :
> On Sun, Jan 27, 2008 at 09:27:58AM +0100, christophelorenz wrote:
>> Rich Felker wrote:
>>> Apparently libbrokenos needs to replace strtod with a working version...
>> Is there an alternative to libbrokenos ?
> Report a bug to MinGW.  This is something you should do anyway.
Are we 100% sure strtod *should* accept 0x1234? On linux debian etch the 
  man page for strtod says this:

        "A  hexadecimal  number consists of a ``0x'' or ``0X'' followed 
by a nonempty sequence of hexadecimal digits possibly con-
        taining a radix character, optionally followed by a binary 
exponent. A binary exponent consists of a ``P'' or ``p'', fol-
        lowed by an optional plus or minus sign, followed by a non-empty 
sequence of decimal digits, and indicates multiplication
        by a power of 2.  At least one of radix character and binary 
exponent must be present."

Seems to me 0x1234 is *not* legal since it contains neither radix nor 
binary exponent...

Of course, man pages are not always the best source for standards!

Note that the official MS (on-web0 doc states:

"strtod expects nptr to point to a string of the following form:

[whitespace] [sign] [digits] [.digits] [ {d | D | e | E}[sign]digits]

A whitespace may consist of space and tab characters, which are ignored; 
sign is either plus (+) or minus (?); and digits are one or more decimal 
digits. If no digits appear before the radix character, at least one 
must appear after the radix character. The decimal digits can be 
followed by an exponent, which consists of an introductory letter (d, D, 
e, or E) and an optionally signed integer. If neither an exponent part 
nor a radix character appears, a radix character is assumed to follow 
the last digit in the string. The first character that does not fit this 
form stops the scan."

So it may be a bit too strong to say its broken, its just C89-compliant 
and not C9x, something MS made no mystery about.

Michel Bardiaux
R&D Director
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