[Ffmpeg-devel] Re: Compilation Issue

[Martin Boehme]

M?ns Rullg?rd wrote:
> Martin Boehme <boehme at inb.uni-luebeck.de> writes:
>>M?ns Rullg?rd wrote:
>>>Martin Boehme <boehme at inb.uni-luebeck.de> writes:
>>>>Rich Felker wrote:
>>>>>On Mon, Sep 26, 2005 at 12:48:02PM +0200, Martin Boehme wrote:
>>>>>>Usman Bashir wrote:
>>>>>>
>>>>>>>Hi!
>>>>>>>	I was seeing the file ("ffmpeg.c") in the ffmpeg source. I found
>>>>>>>almost all the functions "static", can I replace them with
>>>>>>>instance/normal functions. As I think so it will increase the size of
>>>>>>>run time image.
>>>>>>
>>>>>>Huh?
>>>>>>
>>>>>>Don't understand what you're proposing here, but these functions
>>>>>>are static because they are only needed in ffmpeg.c. This file is
>>>>>>an executable, not part of the library.
>>>>>
>>>>>I get the feeling the original poster doesn't understand the C
>>>>>language much at all, and has little/no idea what static means.
>>>>
>>>>Well, that explanation would certainly be consistent with the data... ;-)
>>>
>>>He's probably thinking of Java.
>>
>>Yeah, makes sense... though I still don't see why non-static member
>>functions should be _smaller_ than static member functions -- is this
>>the case for some obscure reason? (Have to admit I don't know a lot
>>about Java's internals.)
> 
> That's not the case.  Behind the scenes, every non-static function
> gets passed a pointer to "this" along with the visible arguments.
> Apart from that, there is no difference between static and non-static
> functions.

So it's just the same as in C++ -- and a static member function should 
thus be slightly faster to call and generate less code at the call site 
than the non-static equivalent.

> (My job involves work on a JVM, so I might know something
> about it.)

So I asked the right person... ;-)

Martin

-- 
Martin B?hme
Inst. f. Neuro- and Bioinformatics
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