[x264-devel] commit: Fix C99ism in r1066 (Jason Garrett-Glaser )

Mathieu Monnier manao at melix.net
Sat Jan 3 12:50:18 CET 2009


> are you sure?
> PGO (Profile guided optimization) has been available in MSVC since 2005
> http://msdn.microsoft.com/en-us/library/aa289170.aspx

As you said in a later post, it was dropped from the free version for 
MSVC 8 (2005) and 9 (2008).

> I would say this remains an (unproven) concept until its viability is
> demonstrated.


> I wouldn't worry to much about the IDE... there's Eclipse, NetBeans, and
> Idea just to name a few providing IDE C/C++ project integration.

But I can bet you none of them has a debugger as useful/powerful as MSVC's.

> when you say "if MSVC provided faster binaries" do you refer to the
> actual generated binaries or the compilation speed of the tools
> themselves (I suspect the former)?

Indeed, I was referring to the encoding times, not compiling times.

> what is the real reason to remove all MSVC support?

None of the active developers use MSVC, so none of them know whenever 
they broke its support. Not supporting C99 makes coding for it slightly 
less easy. No GAS-syntax inline assembly supports is also a problem.

> are we saying that without support for the subset of C99 features
> introduced in r1066 there would be a loss in performance?

No, C99 features only increase maintainability, they don't change 

However, inline assemblies aren't compatible, and that impacts 
performances (inline assembly was disabled for MSVC)

> or is it just a simple dislike for Microsoft (compiler) tools even when
> they are free and/or recent?

I also think that plays a part, at least on some subconscious level.



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