./:	* vec.h (VEC_reserve_exact): Define.
	(vec_gc_p_reserve_exact): Declare.
	(vec_gc_o_reserve_exact): Declare.
	(vec_heap_p_reserve_exact): Declare.
	(vec_heap_o_reserve_exact): Declare.
	(VEC_OP (T,A,reserve_exact)): New static inline function, three
	versions.
	(VEC_OP (T,A,reserve)) [all versions]: Remove handling of
	negative parameter.
	(VEC_OP (T,A,alloc)) [all versions]: Call ...reserve_exact.
	(VEC_OP (T,A,copy)) [all versions]: Likewise.
	(VEC_OP (T,a,safe_grow)) [all versions]: Likewise.
	* vec.c (calculate_allocation): Add exact parameter.  Change all
	callers.
	(vec_gc_o_reserve_1): New static function, from vec_gc_o_reserve.
	(vec_gc_p_reserve, vec_gc_o_reserve): Call vec_gc_o_reserve_1.
	(vec_gc_p_reserve_exact, vec_gc_o_reserve_exact): New functions.
	(vec_heap_o_reserve_1): New static function, from vec_heap_o_reserve.
	(vec_heap_p_reserve, vec_heap_o_reserve): Call vec_heap_o_reserve_1.
	(vec_heap_p_reserve_exact): New function.
	(vec_heap_o_reserve_exact): New function.
cp/:
	* class.c (add_method): Call VEC_reserve_exact rather than passing
	a negative size to VEC_reserve.

From-SVN: r120861