[RPL/2] Major bug in P->R

[BERTRAND Joel]

	Hello,

	Major bug was discovered in P->R intrinsic function when RPL/2 runs in 
degree mode. If you use P->R in this mode, please add COPY before each 
P->R invocation. COPY deletes object on top of stack and replaces it by 
a copy of itself to avoid this bug. It's only a quick and dirty 
workaround and I shall release 4.0.21 as soon as possible.

	If you have a lot of P->R, you can try :

#define p->r copy p->r

	I haven't tested but it should work. All RPL/2 releases that use 
copy-on-write memory management are affected.

	Regards,

	JKB