[krbdev.mit.edu #3060] large default FD_SETSIZE and stack consumption in 1.3.5 krb5 library

[Ken Raeburn via RT]

Could you please try out the attached patch?
It should put the select_state structures in the library into the heap
instead of on the stack.  (There's also an automatic variable in the
KDC, but since that's single-threaded at the moment I assume it's not a
problem.)

The patch is relative to the current development code, not 1.3.5, but I
don't think that code has changed so much that you won't be able to
apply it...

Ken