"_________U___iob\n_________U__abort\n_________U__abort\n_________U__fprintf\n_________U__free\n_________U__malloc\n_________U__malloc\n_________U__memcpy\n_________U__memset\n_________U_dyld_stub_binding_helper\n",
0],
+# Demonstrate that folding changes the ordering of e.g. A, a, and _
+# because while they normally (in the C locale) collate like A, _, a,
+# when using -f, `a' is compared as if it were `A'.
+["21a", '', "A\na\n_\n", "A\n_\na\n", 0],
+["21b", '-f', "A\na\n_\n", "A\na\n_\n", 0],
+["21c", '-f', "a\nA\n_\n", "A\na\n_\n", 0],
+["21d", '-f', "_\na\nA\n", "A\na\n_\n", 0],
+["21e", '-f', "a\n_\nA\n", "A\na\n_\n", 0],
+["21f", '-fs', "A\na\n_\n", "A\na\n_\n", 0],
+["21g", '-fu', "a\n_\n", "a\n_\n", 0],
+
);
sub test_vector