diff --git a/Fltk/fileDialogs.cpp b/Fltk/fileDialogs.cpp
index 06a84e4868c453a5bb096330902c40d2a36cf072..e0d4bad096f42987b8724610bc6bec3901122ea2 100644
--- a/Fltk/fileDialogs.cpp
+++ b/Fltk/fileDialogs.cpp
@@ -1547,7 +1547,7 @@ int pvtuAdaptFileDialog(const char *name)
       Fl_Widget* o = Fl::readqueue();
       if (!o) break;
       if (o == dialog->ok) {
-        bool isBinary;
+        bool isBinary = true;
         switch(dialog->c[1]->value()){
           case 0: isBinary = true; break;
           case 1: isBinary = false; break;