diff --git a/lcl/dialogs.pp b/lcl/dialogs.pp
index b5ab2f546d..438920f426 100644
--- a/lcl/dialogs.pp
+++ b/lcl/dialogs.pp
@@ -520,7 +520,7 @@ type
   TTaskDialogCommonButton = (tcbOk, tcbYes, tcbNo, tcbCancel, tcbRetry, tcbClose);
   TTaskDialogCommonButtons = set of TTaskDialogCommonButton;
 
-  TTaskDlgClickEvent = procedure(Sender: TObject; ModalResult: TModalResult; var CanClose: Boolean) of object;
+  TTaskDlgClickEvent = procedure(Sender: TObject; AModalResult: TModalResult; var ACanClose: Boolean) of object;
 
   TTaskDialogIcon = (tdiNone, tdiWarning, tdiError, tdiInformation, tdiShield, tdiQuestion);
 
@@ -610,7 +610,7 @@ type
     function ButtonIDToModalResult(const AButtonID: Integer): TModalResult;
   protected
     function DoExecute(ParentWnd: HWND): Boolean; dynamic;
-    procedure DoOnButtonClicked(AModalResult: Integer; var CanClose: Boolean); dynamic;
+    procedure DoOnButtonClicked(AModalResult: Integer; var ACanClose: Boolean); dynamic;
   public
     constructor Create(AOwner: TComponent); override;
     destructor Destroy; override;
diff --git a/lcl/include/taskdialog.inc b/lcl/include/taskdialog.inc
index 58262cb96b..067f62f546 100644
--- a/lcl/include/taskdialog.inc
+++ b/lcl/include/taskdialog.inc
@@ -239,10 +239,10 @@ begin
 end;
 
 procedure TCustomTaskDialog.DoOnButtonClicked(AModalResult: Integer;
-  var CanClose: Boolean);
+  var ACanClose: Boolean);
 begin
   if Assigned(FOnButtonClicked) then
-    FOnButtonClicked(Self, AModalResult, CanClose);
+    FOnButtonClicked(Self, AModalResult, ACanClose);
 end;
 
 procedure TCustomTaskDialog.DoOnButtonClickedHandler(Sender: PTaskDialog;