Re: Does Casting Slow a Program Down?

On Wed, 31 Jan 2007 15:04:29 +0000, Chris Dollin <chris.dollin@xxxxxx>
wrote:
PeterOut wrote:
If I had code like this.

unsigned short usLimit=10
int a[10], i;

for (i=0; i<(int)usLimit; ++i)
{
a[i]=(int)usLimit;
}

would it run slower than this?

int a[10], i, iLimit=10;

for (i=0; i<iLimit; ++i)
{
a[i]=iLimit;
}

It might, but it would have nothing to do with the casts,
since they're both unnecessary -- `usLimit` is
converted from `unsigned short` to `int` regardless.

Right, 'unsigned short' is prometed to 'int' anyway. The casts are
probably in the code because the compiler (hopefully) issues a warning
otherwise. So the real question is whether it makes sense to use
'unsigned short' instead of 'int' in this case.

Best regards,
Roland Pibinger
.

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