constant expressions change? CVS build failure on IA64

[Boehm, Hans]

CVS gcc4.0 no longer seems to accept the expression in

# define _SC_GR0_OFFSET	\
	(((char *) &((struct sigcontext *) 0)->sc_gr[0]) - (char *) 0)

in Linux/IA64 sys/ucontext.h as a constant.  This eventually results
in a gcc build failure.  (A workaround is to change the header file to use
the non-gcc definition.)

Was this change intentional?

Hans