* test-suite/tests/sort.test: Added. Both tests in that file did

	* test-suite/tests/sort.test: Added.  Both tests in that file did
	fail (one even with a segfault) with CVS guile before the recent
	changes to libguile/sort.c.

	* libguile/sort.c: Replaced hand-made trampline code by the new
	official mechanism from eval.c.  This fixes a segfault in the new
	test file test-suite/tests/sort.test.

	(quicksort, compare_function, scm_restricted_vector_sort_x,
	scm_sorted_p, scm_merge, scm_merge_list_x, scm_merge_x,
	scm_merge_list_step, scm_sort_x, scm_sort, scm_merge_vector_x,
	scm_merge_vector_step, scm_stable_sort_x, scm_stable_sort,
	scm_sort_list_x, scm_sort_list): Use trampoline mechanism from
	eval.c.

	(subr2less, lsubrless, closureless, applyless, scm_cmp_function,
	cmp_fun_t): Removed.

	(compare_function): Added.

	* libguile/sort.c (quicksort, SWAP, stack_node): Replaced pointer
	arithmetics with index arithmetics.  Changed quicksort to work on
	an array of SCM values instead of an array of characters.  Avoid
	bytewise copying of SCM elements.  Avoid allocating memory on the
	stack with alloca.  Fixed some comments.