This feature is new in the Solaris Express 3/04 release and in the Solaris 9 9/04 release.
The semantics of the uc_stack member of the ucontext_t structure have changes as they apply to inputs to the makecontext(3C) libc library function. Binary compatibility is preserved between previous versions of Solaris and the Solaris 10 OS.
Applications that use this interface must be updated before they are recompiled for the Solaris 10 OS. See the makecontext(3C) man page for further information.