@itemize
@item
This function is missing on some platforms:
-MacOS X 10.5, OpenBSD 3.8, Cygwin, mingw, Interix 3.5, BeOS.
+MacOS X 10.4, OpenBSD 3.8, Cygwin, mingw, Interix 3.5, BeOS.
@item
The effects of this call are system and compiler optimization dependent,
since it restores the contents of register-allocated variables but not