1.3.29 $POINTERMATH : Allow use of pointer math

This boolean directive enables or disables the use of pointer arithmetic in expressions involving pointers. When enabled, the difference of 2 pointers is a valid integer expression, and an integer value can be added to a pointer value. By default, POINTERMATH is on.

The following

{$POINTERMATH OFF}  
unit MyUnit;

tells the compiler to give an error whenever pointer math appears in an expression.