diff --git a/docs/latex/wx/snglinst.tex b/docs/latex/wx/snglinst.tex
index 16544113cb..3cae29f168 100644
--- a/docs/latex/wx/snglinst.tex
+++ b/docs/latex/wx/snglinst.tex
@@ -30,6 +30,9 @@ bool MyApp::OnInit()
     {
         wxLogError(_("Another program instance is already running, aborting."));
 
+        delete m_checker; // OnExit() won't be called if we return false
+        m_checker = NULL;
+
         return false;
     }