* gdb.base/signals.exp: Setup "alpha-*-osf2*" xfail for

	* gdb.base/signals.exp: Setup "alpha-*-osf2*" xfail for
	"bt in signals.exp".
	* gdb.base/a1-selftest.exp: Add alpha-dec-osf2 setup_xfail for
	"step over execarg initialization" and
 	"step over corearg initialization".
	* gdb.base/ptype.c (main): Declare malloc as a "char *" for systems
	with sizeof(pointer) > sizeof(int).  Avoid "void *" or include files.