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--- a/src/qtgui/rclmain_w.h
+++ b/src/qtgui/rclmain_w.h
@@ -30,6 +30,8 @@
 #include "spell_w.h"
 #include "refcntr.h"
 #include "pathut.h"
+
+class ExecCmd;
 
 #if QT_VERSION < 0x040000
 #include "rclmain.h"
@@ -130,6 +132,7 @@
     QTimer         *periodictimer;
 
     vector<TempFile>  m_tempfiles;
+    vector<ExecCmd*>  m_viewers;
     map<QString, int> m_stemLangToId;
     vector<string>    m_catgbutvec;
     int               m_idNoStem;