theora dev - Mar 2010 - Build warnings

Hi all,

I've recently decided to take a look at Theora for the first time. The 1.1.1
release compiles fine, but the compiler generates a fairly large number of
warnings about "suggest parentheses around + or - inside shift".
I've had a look at a few of these and sometimes it isn't obvious what is
meant to happen. I guess the code is all correct though as I'm sure somebody
would have done something about this before if it wasn't.

Maybe I'll just edit the code to put the parentheses in to keep the compiler
quiet and then submit the changes to the SVN?

Regards,
Stuart
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Stuart Fisher wrote:
> 1.1.1 release compiles fine, but the compiler generates a fairly large
> number of warnings about "suggest parentheses around + or - inside
What compiler are you using? The code should disable this warning for
both MSVC and gcc.
> Maybe I'll just edit the code to put the parentheses in to keep the
> compiler quiet and then submit the changes to the SVN?
Please don't.

Thank you for bringing this up, Stuart!  I've been meaning to mention this
but it slipped my mind...	The Theora project (and I think all the Ogg projects
in general) generates a lot of warnings when compiled.  Obviously all these
warnings turn out to describe harmless things but it's better to have a
project with no warnings so that when a change is made and a warning for a real
problem gets reported, it's not lost in a sea of irrelevant warnings...	The
problem I had to solve was actually a little more serious than a mere warning. 
In the code, there are a lot of local variable declarations like so:

int func() {	int local_var = local_var;
	// do stuff}

	I'm guessing that this self initialization trick is supposed to trick the
compiler into not reporting an uninitialized variable for variables that are
only conditionally used.  However, when compiled for MS Windows using VC 2005 in
debug mode, these initializations fail runtime checks and consequently throw
exceptions.  This is really irritating when trying to debug code using Theora. 
I actually had to run through all the code changing these initializations to
something the compiler preferred like simply zeroing them out.  It would be nice
if the official code base simply did this to begin with...	Again, it would be
nice if the various Ogg projects didn't report any warnings when compiled. 
You could almost do this just by throwing some brackets and explicit casts in
the code...
	Finally, and a little off topic, but considering the lack of comprehensive
documentation and tutorials for the various Ogg APIs, it would be a good idea
for the example code, which frankly act like reference implementations, to be a
little more verbose.  Variable names like "vi," "vt,"
"vc" etc... help to confuse the reader and obfuscate the code.  They
have no place in an example program...	Thank you...
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I want to decode the video frames to a smaller size. Decoding them at full 
size and then scaling them down to the size I want isn't very efficient, but
I can't see any way of avoiding that with the current decoding functions.

I'm going to try and figure out how easy it is to make theora do this.
I'm
wondering if anyone has tried this before or if there are any reasons why it 
can't be done?