"VOLATILE" IS VERY C0NFUSING

Is it required in the following case to declare PortPin as volatile :

sbit PortPin = P3^7 ;

/////// check k/b ststus

If (PortPin = 0 )
{ ///// some kb routine

do

while (PortPin ==0)
}

Is it required in the following case to declare PortPin as volatile :

sbit PortPin = P3^7 ;

/////// check k/b ststus

If (PortPin = 0 )
{ ///// some kb routine

do

while (PortPin ==0)
}

"Is it required in the following case to declare PortPin as volatile"

I seem to recall some time ago (years ago?) Keil saying that SFRs and their bit objects are implicitly volatile. I could not find a reference to that in an extremely short time searching. I'll try again when I have time.

Yes, I seem to recall that, too!

I also seem to recall not being able to find it (clearly) documented anywhere...