ck.
<LI>The stack(s).  In the case of a single-threaded application,
on most platforms this
is done by scanning the memory between (an approximation of) the current
stack pointer and <TT>GC_stackbottom</tt>.  (For Itanium, the register stack
scanned separately.)  The <TT>GC_stackbottom</tt> variable is set in
a highly platform-specific way depending on the appropriate configuration
information in <TT>gcconfig.h</tt>.  Note that the currently active
stack needs to be scanned carefully, since callee-save regi