gracefully deal with "eval" exceptions that occur during AST reduction

src/script_opt/Reduce.cc

@@ -14,6 +14,20 @@
 
 namespace zeek::detail {
 
+StmtPtr Reducer::Reduce(StmtPtr s)
+	{
+	reduction_root = std::move(s);
+
+	try
+		{
+		return reduction_root->Reduce(this);
+		}
+	catch ( InterpreterException& e )
+		{
+		/* Already reported. */
+		return reduction_root;
+		}
+	}
 
 ExprPtr Reducer::GenTemporaryExpr(const TypePtr& t, ExprPtr rhs)
 	{

src/script_opt/Reduce.h

@@ -18,11 +18,7 @@ class Reducer {
 public:
 	Reducer()	{ }
 
-	StmtPtr Reduce(StmtPtr s)
+	StmtPtr Reduce(StmtPtr s);
-		{
-		reduction_root = std::move(s);
-		return reduction_root->Reduce(this);
-		}
 
 	const DefSetsMgr* GetDefSetsMgr() const		{ return mgr; }
 	void SetDefSetsMgr(const DefSetsMgr* _mgr)	{ mgr = _mgr; }