Remove some unused vars.

pcbnew/dialogs/dialog_footprint_checker.cpp

@@ -89,15 +89,11 @@ void DIALOG_FOOTPRINT_CHECKER::runChecks()
 {
     BOARD*     board = m_frame->GetBoard();
     FOOTPRINT* footprint = board->GetFirstFootprint();
-    wxString   msg;
 
     deleteAllMarkers();
 
     if( !footprint )
-    {
-        msg = _( "No footprint loaded." );
         return;
-    }
 
     auto errorHandler =
             [&]( const BOARD_ITEM* aItemA, const BOARD_ITEM* aItemB, const BOARD_ITEM* aItemC,

pcbnew/dialogs/panel_fp_lib_table.cpp

@@ -440,8 +440,6 @@ void PANEL_FP_LIB_TABLE::populatePluginList()
 
 bool PANEL_FP_LIB_TABLE::verifyTables()
 {
-    wxString msg;
-
     for( int page = 0 ; page < (int) m_notebook->GetPageCount(); ++page )
     {
         WX_GRID* grid = get_grid( page );

pcbnew/drc/rule_editor/panel_drc_rule_editor.cpp

@@ -480,9 +480,8 @@ void PANEL_DRC_RULE_EDITOR::onScintillaCharAdded( wxStyledTextEvent& aEvent )
 
     m_textConditionCtrl->SearchAnchor();
 
-    wxString rules = m_textConditionCtrl->GetText();
-    int      currentPos = m_textConditionCtrl->GetCurrentPos();
-    int      startPos = 0;
+    int currentPos = m_textConditionCtrl->GetCurrentPos();
+    int startPos = 0;
 
     for( int line = m_textConditionCtrl->LineFromPosition( currentPos ); line > 0; line-- )
     {