[Xotcl] XoTCL 1.0 on AIX

[Jeff Hobbs]

> - the choice of ALLOCA is not good vor Visual C/C++ 5.0. Choosing MALLOC
> seems to be good and should be good for all IBM compilers

No, alloca != malloc.  alloca uses stack and auto-frees.  alloca should
also be available on AIX by including either -lc or -lbsd.

> - the compilers were formerly versioned with hex codes now they are with
> decimal codes which regrettably sabotages any scalar comparison so #if
> __IBMC__ >= 0x306 won't work. This makes it hard to distinguish between
> various IBM C compilers. If you insist compare only with = not with > or
<.

Ack, except for compiler bugs, what would want want to care about the
version of the compiler for?

> - the shared library configuration is not correctly used in the makefiles.
> see description below

It would probably help if someone upgraded this to TEA2 build system.
It isn't a big modification, but it does have notable improvements like
not requiring that the extension be built with the same compiler setup
as Tcl itself was.  This is important on "odd" platforms like AIX, where
gcc and xlc/cc can greatly disagree.

  Jeff Hobbs                     The Tcl Guy
  Senior Developer               http://www.ActiveState.com/
      Tcl Support and Productivity Solutions