In 64-bit LispWorks and on x86 platforms the compiler optimizes tail calls unless
debug
is 3, or
dynamic-extent
allocation (so it is not really a tail call)On all other platforms the compiler optimizes tail calls unless 1.) or 2.) above apply, or
&optional
/
&rest
/
&key
) parameters in the calling function.
&rest
/
&key
parameters.LispWorks User Guide and Reference Manual - 21 Dec 2011