Move unnecessarily inlined implementations to otherwise empty cpp file

This provides guidance to the compiler on where to place virtual tables, and
also silences a linker warning.

Author: tautschnig

src/util/decision_procedure.cpp

@@ -11,4 +11,10 @@ Author: Daniel Kroening, [email protected]
 
 #include "decision_procedure.h"
 
+decision_proceduret::decision_proceduret(const namespacet &_ns) : ns(_ns)
+{
+}
 
+decision_proceduret::~decision_proceduret()
+{
+}

src/util/decision_procedure.h

@@ -20,9 +20,9 @@ class namespacet;
 class decision_proceduret:public messaget
 {
 public:
-  explicit decision_proceduret(const namespacet &_ns):ns(_ns)
-  {
-  }
+  explicit decision_proceduret(const namespacet &_ns);
+
+  virtual ~decision_proceduret();
 
   // get a value from satisfying instance if satisfiable
   // returns nil if not available

src/util/dstring.cpp

@@ -10,3 +10,8 @@ Author: Daniel Kroening, [email protected]
 /// Container for C-Strings
 
 #include "dstring.h"
+
+std::ostream &dstringt::operator<<(std::ostream &out) const
+{
+  return out << as_string();
+}

src/util/dstring.h

@@ -123,10 +123,7 @@ class dstringt final
 
   // output
 
-  std::ostream &operator<<(std::ostream &out) const
-  {
-    return out << as_string();
-  }
+  std::ostream &operator<<(std::ostream &out) const;
 
   // non-standard