EncodingContext's solver needs to be set dynamically

libsolidity/formal/EncodingContext.h

@@ -36,7 +36,7 @@ namespace smt
 class EncodingContext
 {
 public:
-	EncodingContext(std::shared_ptr<SolverInterface> _solver);
+	EncodingContext();
 
 	/// Resets the entire context except for symbolic variables which stay
 	/// alive because of state variables and inlined function calls.
@@ -46,6 +46,14 @@ public:
 	/// To be used before a model checking engine starts.
 	void clear();
 
+	/// Sets the current solver used by the current engine for
+	/// SMT variable declaration.
+	void setSolver(std::shared_ptr<SolverInterface> _solver)
+	{
+		solAssert(_solver, "");
+		m_solver = _solver;
+	}
+
 	/// Forwards variable creation to the solver.
 	Expression newVariable(std::string _name, SortPointer _sort)
 	{
@@ -133,7 +141,11 @@ public:
 	void pushSolver();
 	void popSolver();
 	void addAssertion(Expression const& _e);
-	std::shared_ptr<SolverInterface> solver() { return m_solver; }
+	std::shared_ptr<SolverInterface> solver()
+	{
+		solAssert(m_solver, "");
+		return m_solver;
+	}
 	//@}
 
 private: