diff --git a/src/edif.cpp b/src/edif.cpp
index e8f32e8bbb549e79d9510ccbb4cb3f560e079a68..c663595a035e322997693d2591c17d7d76ed37b4 100644
--- a/src/edif.cpp
+++ b/src/edif.cpp
@@ -1130,7 +1130,7 @@ void NEdif::Plot( bool add )
                              e->P()->xco.str(), e->P()->yco.str(),
                              "curve file "+strg(k)+" scan "+strg(j) );
             } else if ( fc ) {
-                double arg, val;
+                double x, y;
                 int npts = 100;
                 double delta0 = 1.0/(npts-1.e-10);
                 double delta = delta0;
@@ -1139,10 +1139,11 @@ void NEdif::Plot( bool add )
                 double pos = 0;
                 bool was_inside = false;
                 bool is_inside;
+                double was_x, was_y;
                 while(1){
-                    arg = NPlot::X.R.plotcoord2value( NPlot::X.log, pos );
-                    val = fc->T->tree_curve_val_sca( arg, k, j );
-                    is_inside = NPlot::Y.R.contained( val );
+                    x = NPlot::X.R.plotcoord2value( NPlot::X.log, pos );
+                    y = fc->T->tree_curve_val_sca( x, k, j );
+                    is_inside = NPlot::Y.R.contained( y );
                     if( !is_inside ){
                         if( was_inside ){
                         }
@@ -1154,7 +1155,7 @@ void NEdif::Plot( bool add )
                         *s = S;
                         s->Clear();
                     }
-                    s->push_back( arg, val );
+                    s->push_back( x, y );
                 incr_pos:
                     was_inside = is_inside;
                     if( pos>= 1 )