[FFmpeg-devel] check_func() from configure & "math.h"

Måns Rullgård mans
Wed Aug 19 12:23:15 CEST 2009


ami_stuff <ami_stuff at o2.pl> writes:

>> > I have defined functions like lrint/lrintf/log2/round/roundf in the
>> > "math.h" include.  When I run "configure", it can't find them, so I
>> > must always define them manually to 1 in the "config.h" file.
>> >
>> > Maybe it would be possible to also add check for functions in the
>> > "math.h", not only in the linkable libs?
>> 
>> The standard requires those functions in the library.  Redo your homework.
>
> But functions in library probably would be slower.

Read the spec.  If you think you did, do it again.  Repeat until you
*understand* it.

You're allowed to provide whatever magic you like, but you must
provide external definitions for these functions in the library as
well.

Besides, doesn't gcc have builtins for these functions anyway?

-- 
M?ns Rullg?rd
mans at mansr.com



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