Extends the current stack.
extend-current-stack &optional how-much => size
What percentage the stack should be extended by. The default is 50.
The new size of the stack, after extending.
Extend the current stack by the given percentage.
In LispWorks 4.4 and previous on Windows and Linux platforms,
extend-current-stack is not implemented. This is fixed in LispWorks 5.0 and later.
To double the size of the current stack:
LispWorks User Guide and Reference Manual - 13 Feb 2015