[FFmpeg-devel] Moving if(constant expression) to preprocessor?

[Axel Holzinger]

Hi Ramiro,
Ramiro Polla wrote:
> On Sat, Sep 18, 2010 at 2:32 PM, Bobby Bingham 
> <uhmmmm at gmail.com> wrote:
> > Why do you want to compile without dead code elimination? ?
> I don't see 
> > what the benefit is. ?And without a compelling reason, I 
> don't think 
> > it's worth obfuscating the code.
> 
> I might be guessing wrong here but I believe he's trying to 
> build FFmpeg with ICL (Intel C compiler for Windows), which 
> tries to mimic MSVC, which fails on such code.

That has nothing to do with ICC, ICL or MSVC. ICL compiles the code,
with dead code elimination, that's not the problem. It has also
nothing to do with mimicing anything. ICL mimics MSVC only for
compiler switches. That's a different story.

Currently I can compile FFmpeg using ICL. What is not possible -
without a conditional if macro - is disabling optimisations. And this
to me is a restriction I don't see the benefit of. We're talking about
a debug build with --disable-optimizations. We're not talking about
the release build.

The only costs for making it right is ten lines of #defines. And what
we get is a very useful tool and cleaner code, because it doesn't rely
on compiler specifics to make the build succeed.

Cheers
Axel