Initialize at declaration instead of construction

Should another constructor be added in the future (copy, move, default,
overload of existing constructor), one set of default arguments will
already be present.

Author: romainbrenguier

src/solvers/prop/prop_conv.h

@@ -72,10 +72,6 @@ class prop_conv_solvert:public prop_convt
 public:
   prop_conv_solvert(const namespacet &_ns, propt &_prop):
     prop_convt(_ns),
-    use_cache(true),
-    equality_propagation(true),
-    freeze_all(false),
-    post_processing_done(false),
     prop(_prop) { }
 
   virtual ~prop_conv_solvert() { }
@@ -106,9 +102,9 @@ class prop_conv_solvert:public prop_convt
   // get literal for expression, if available
   virtual bool literal(const exprt &expr, literalt &literal) const;
 
-  bool use_cache;
-  bool equality_propagation;
-  bool freeze_all; // freezing variables (for incremental solving)
+  bool use_cache = true;
+  bool equality_propagation = true;
+  bool freeze_all = false; // freezing variables (for incremental solving)
 
   virtual void clear_cache() { cache.clear();}
 
@@ -126,7 +122,7 @@ class prop_conv_solvert:public prop_convt
 protected:
   virtual void post_process();
 
-  bool post_processing_done;
+  bool post_processing_done = false;
 
   // get a _boolean_ value from counterexample if not valid
   virtual bool get_bool(const exprt &expr, tvt &value) const;