diff --git a/spot/taalgos/tgba2ta.cc b/spot/taalgos/tgba2ta.cc
index 5355c3cc3..5c4d006c1 100644
--- a/spot/taalgos/tgba2ta.cc
+++ b/spot/taalgos/tgba2ta.cc
@@ -102,33 +102,13 @@ namespace spot
                 ++it_trans;
               }
 
-          if (transitions_to_livelock_states)
-            {
-              state_ta_explicit::transitions::iterator it_trans;
-
-              for (it_trans = transitions_to_livelock_states->begin();
-                   it_trans != transitions_to_livelock_states->end();
-                   ++it_trans)
-                {
-                  if (artificial_livelock_acc_state)
-                    {
-                      testing_automata->create_transition
-                        (source,
-                         (*it_trans)->condition,
-                         (*it_trans)->acceptance_conditions,
-                         artificial_livelock_acc_state, true);
-                    }
-                  else
-                    {
-                      testing_automata->create_transition
-                        (source,
-                         (*it_trans)->condition,
-                         (*it_trans)->acceptance_conditions,
-                         ((*it_trans)->dest)->stuttering_reachable_livelock,
-                         true);
-                    }
-                }
-            }
+          for (auto* trans: *transitions_to_livelock_states)
+            testing_automata->create_transition
+              (source, trans->condition,
+               trans->acceptance_conditions,
+               artificial_livelock_acc_state ?
+               artificial_livelock_acc_state :
+               trans->dest->stuttering_reachable_livelock, true);
         }
       delete transitions_to_livelock_states;
 
diff --git a/spot/twaalgos/are_isomorphic.cc b/spot/twaalgos/are_isomorphic.cc
index 44b220c0d..127b5c6fa 100644
--- a/spot/twaalgos/are_isomorphic.cc
+++ b/spot/twaalgos/are_isomorphic.cc
@@ -30,19 +30,19 @@
 namespace
 {
   typedef spot::twa_graph::graph_t::edge_storage_t tr_t;
-  bool
+  static bool
   tr_t_less_than(const tr_t& t1, const tr_t& t2)
   {
     return t1.cond.id() < t2.cond.id();
   }
 
-  bool
+  static bool
   operator!=(const tr_t& t1, const tr_t& t2)
   {
     return t1.cond.id() != t2.cond.id();
   }
 
-  bool
+  static bool
   are_isomorphic_det(const spot::const_twa_graph_ptr aut1,
                      const spot::const_twa_graph_ptr aut2)
   {
@@ -135,14 +135,12 @@ namespace spot
     trival autdet = aut->prop_deterministic();
     if (ref_deterministic_)
       {
-        if (autdet || (!autdet && spot::is_deterministic(aut)))
-          return are_isomorphic_det(ref_, aut);
-      }
-    else
-      {
-        if (autdet || nondet_states_ != spot::count_nondet_states(aut))
+        if (!spot::is_deterministic(aut))
           return false;
+        return are_isomorphic_det(ref_, aut);
       }
+    if (autdet || nondet_states_ != spot::count_nondet_states(aut))
+      return false;
 
     auto tmp = make_twa_graph(aut, twa::prop_set::all());
     spot::canonicalize(tmp);
diff --git a/spot/twaalgos/ltl2tgba_fm.cc b/spot/twaalgos/ltl2tgba_fm.cc
index 97318e200..5e779db1e 100644
--- a/spot/twaalgos/ltl2tgba_fm.cc
+++ b/spot/twaalgos/ltl2tgba_fm.cc
@@ -1781,15 +1781,11 @@ namespace spot
           }
 
         // Apply the fair-loop approximation if requested.
-        if (fair_loop_approx_)
-          {
+        if (fair_loop_approx_
             // If the source cannot possibly be part of a fair
             // loop, make all possible promises.
-            if (fair_loop_approx_
-                && f != formula::tt()
-                && !pflc_.check(f))
-              t.symbolic &= all_promises_;
-          }
+            && !f.is_tt() && !pflc_.check(f))
+          t.symbolic &= all_promises_;
 
         // Register the reverse mapping if it is not already done.
         if (b2f_.find(t.symbolic) == b2f_.end())