random.tcc (struct _To_Unsigned_Type): Add.

2006-07-14  Paolo Carlini  <pcarlini@suse.de>

	* include/tr1/random.tcc (struct _To_Unsigned_Type): Add.
	(subtract_with_carry<>::seed(_Gen&, false_type)): Use an
	unsigned type in the loop, fix factor multiplier, take g
	invocations modulo 2^32.

	* include/tr1/random.tcc (subtract_with_carry<>::
	seed(unsigned long)): Fix value == 0 special case.

	* include/tr1/random (struct _Shift): Fix for large shifts.

From-SVN: r115439