*: use llist_pop for traverse-and-free list operation

function                                             old     new   delta
append_file_list_to_list                             109     111      +2
udhcpc_main                                         2414    2413      -1
run_parts_main                                       325     324      -1
od_main                                             2324    2323      -1
getopt_main                                          709     707      -2
env_main                                             253     251      -2
sed_main                                             659     656      -3
ps_main                                              522     519      -3
traceroute_main                                     3960    3954      -6
sort_main                                            844     838      -6
diff_main                                            866     858      -8
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/10 up/down: 2/-33)            Total: -31 bytes

3 files changed, 3 insertions, 7 deletions

diff --git a/coreutils/env.c b/coreutils/env.c
index e21740d98..8d8753e8b 100644
--- a/coreutils/env.c
+++ b/coreutils/env.c
@@ -62,8 +62,7 @@ int env_main(int argc ATTRIBUTE_UNUSED, char **argv)
                 environ = cleanenv;
         } else {
                 while (unset_env) {
-                        unsetenv(unset_env->data);
-                        unset_env = unset_env->link;
+                        unsetenv(llist_pop(&unset_env));
                 }
         }
 
diff --git a/coreutils/od_bloaty.c b/coreutils/od_bloaty.c
index 5e2287534..ce963db8a 100644
--- a/coreutils/od_bloaty.c
+++ b/coreutils/od_bloaty.c
@@ -1281,8 +1281,7 @@ int od_main(int argc, char **argv)
         if (opt & OPT_o) decode_format_string("o2");
         //if (opt & OPT_t)...
         while (lst_t) {
-                decode_format_string(lst_t->data);
-                lst_t = lst_t->link;
+                decode_format_string(llist_pop(&lst_t));
         }
         if (opt & OPT_v) verbose = 1;
         if (opt & OPT_x) decode_format_string("x2");
diff --git a/coreutils/sort.c b/coreutils/sort.c
index 12b463a6d..1f531fb76 100644
--- a/coreutils/sort.c
+++ b/coreutils/sort.c
@@ -314,7 +314,7 @@ int sort_main(int argc ATTRIBUTE_UNUSED, char **argv)
                         0
                 };
                 struct sort_key *key = add_key();
-                char *str_k = lst_k->data;
+                char *str_k = llist_pop(&lst_k);
                 const char *temp2;
 
                 i = 0; /* i==0 before comma, 1 after (-k3,6) */
@@ -344,8 +344,6 @@ int sort_main(int argc ATTRIBUTE_UNUSED, char **argv)
                                 str_k++;
                         }
                 }
-                /* leaking lst_k... */
-                lst_k = lst_k->link;
         }
 #endif
         /* global b strips leading and trailing spaces */