!TITLE Stack corruption on READ SYMBOL

There is a compiler bug which causes corruption to the data stack on calls to
READ SYMBOL (which is treated in a peculiar fashion), if READ SYMBOL is the
only routine called within a routine or block. A temporary fix is to include
a call to some other routine.

Note that the dummy routine must in principle be reachable, or the compiler will
remove its call and perform the bad optimisation used for read symbol.