diff -up gdl-0.9.8/src/basic_fun.cpp.catch gdl-0.9.8/src/basic_fun.cpp
--- gdl-0.9.8/src/basic_fun.cpp.catch	2018-03-26 03:57:27.000000000 -0600
+++ gdl-0.9.8/src/basic_fun.cpp	2018-03-26 16:54:13.508994366 -0600
@@ -1505,7 +1505,7 @@ namespace lib {
 	if( !compileFlags) GDLInterpreter::ReportCompileError( ex);
 	return new DIntGDL( 0);
       }
-    catch( ANTLRException ex)
+    catch( ANTLRException& ex)
       {
 	if( !compileFlags) cerr << "EXECUTE: Lexer/Parser exception: " <<  
 			     ex.getMessage() << endl;
@@ -1529,7 +1529,7 @@ namespace lib {
 	return new DIntGDL( 0);
       }
 
-    catch( ANTLRException ex)
+    catch( ANTLRException& ex)
       {
 	if( !compileFlags) cerr << "EXECUTE: Compiler exception: " <<  
 			     ex.getMessage() << endl;
@@ -1570,7 +1570,7 @@ namespace lib {
 			     ex.getMessage() << endl;
 	return new DIntGDL( 0);
       }
-    catch( ANTLRException ex)
+    catch( ANTLRException& ex)
       {
 	caller->ResizeForLoops( nForLoopsIn);
 		
@@ -6456,7 +6456,7 @@ template <typename Ty, typename T2>  sta
 	    try {
 	      oStruct = e->GetObjHeap( objRef);
 	    }
-	    catch ( GDLInterpreter::HeapException )
+	    catch ( GDLInterpreter::HeapException& )
 	      { // non valid object
 		if( count)
 		  e->SetKW( countIx, new DLongGDL( 0));
diff -up gdl-0.9.8/src/dinterpreter.cpp.catch gdl-0.9.8/src/dinterpreter.cpp
--- gdl-0.9.8/src/dinterpreter.cpp.catch	2018-03-26 03:57:27.000000000 -0600
+++ gdl-0.9.8/src/dinterpreter.cpp	2018-03-26 16:53:15.635298830 -0600
@@ -143,7 +143,7 @@ DStructGDL* GDLInterpreter::ObjectStruct
   try {
     oStructGDL= GetObjHeap( o);
   }
-  catch ( HeapException)
+  catch ( HeapException&)
     {
       throw GDLException( mp, "Object not valid: "+Name(self));
     }
@@ -578,12 +578,12 @@ bool GDLInterpreter::CompileFile(const s
 	return false;
       }	
   }
-  catch( GDLException e)
+  catch( GDLException& e)
     {
       ReportCompileError( e, f);
       return false;
     }
-  catch( ANTLRException e)
+  catch( ANTLRException& e)
     {
       cerr << "Lexer/Parser exception: " <<  e.getMessage() << endl;
       return false;
@@ -612,13 +612,13 @@ bool GDLInterpreter::CompileFile(const s
 
       if( treeParser.ActiveProCompiled()) RetAll();
     }
-  catch( GDLException e)
+  catch( GDLException& e)
     {
       ReportCompileError( e, f);
       if( treeParser.ActiveProCompiled()) RetAll();
       return false;
     }
-  catch( ANTLRException e)
+  catch( ANTLRException& e)
     {
       cerr << "Compiler exception: " <<  e.getMessage() << endl;
       if( treeParser.ActiveProCompiled()) RetAll();
@@ -705,7 +705,7 @@ DInterpreter::CommandCode DInterpreter::
 		// default is more verbose
 		CompileFile( argstr); //, origstr); 
 	      }
-	      catch( RetAllException)
+	      catch( RetAllException&)
 		{
 		  // delay the RetAllException until finished
 		  retAll = true;
@@ -771,7 +771,7 @@ DInterpreter::CommandCode DInterpreter::
 		// default is more verbose
 		CompileFile( argstr); //, origstr); 
 	      }
-	      catch( RetAllException)
+	      catch( RetAllException&)
 		{
 		  // delay the RetAllException until finished
 		  retAll = true;
diff -up gdl-0.9.8/src/getfmtast.cpp.catch gdl-0.9.8/src/getfmtast.cpp
--- gdl-0.9.8/src/getfmtast.cpp.catch	2018-03-26 03:57:27.000000000 -0600
+++ gdl-0.9.8/src/getfmtast.cpp	2018-03-26 16:54:32.793899215 -0600
@@ -68,15 +68,15 @@ RefFMTNode GetFMTAST( DString fmtString)
     cout << endl;
 #endif
   }
-  catch( GDLException ex)
+  catch( GDLException& ex)
     {
       throw GDLException("Format: "+ex.getMessage());
     }
-  catch( antlr::ANTLRException ex)
+  catch( antlr::ANTLRException& ex)
     {
       throw GDLException("Format parser: "+ex.getMessage());
     }
-  catch( exception ex)
+  catch( exception& ex)
     {
       throw GDLException("Format exception: "+string(ex.what()));
     }