diff --git a/ide/lazarusidestrconsts.pas b/ide/lazarusidestrconsts.pas
index 875f787d75..27a82afa37 100644
--- a/ide/lazarusidestrconsts.pas
+++ b/ide/lazarusidestrconsts.pas
@@ -722,6 +722,9 @@ resourcestring
     +'be saved before building%sIf you set the Test Directory in the '
     +'IDE options,%syou can create new projects and build them at '
     +'once.%sSave project?';
+  lisBusy = 'Busy';
+  lisCanNotTestTheCompilerWhileDebuggingOrCompiling = 'Can not test the '
+    +'compiler while debugging or compiling.';
   lisProjectSuccessfullyBuilt = 'Project %s%s%s successfully built';
   lisExecutingCommandBefore = 'Executing command before';
   lisExecutingCommandAfter = 'Executing command after';
diff --git a/ide/main.pp b/ide/main.pp
index 17e812e019..8906cefc96 100644
--- a/ide/main.pp
+++ b/ide/main.pp
@@ -6954,7 +6954,11 @@ function TMainIDE.DoTestCompilerSettings(
   TheCompilerOptions: TCompilerOptions): TModalResult;
 begin
   Result:=mrCancel;
-  if (Project1=nil) or (ToolStatus<>itNone) then exit;
+  if (Project1=nil) or (ToolStatus<>itNone) then begin
+    IDEMessageDialog(lisBusy,
+      lisCanNotTestTheCompilerWhileDebuggingOrCompiling, mtInformation, [mbOk]);
+    exit;
+  end;
 
   // change tool status
   CheckCompilerOptsDlg:=TCheckCompilerOptsDlg.Create(nil);