Don't access possibly deleted wxTimer in GTK callback.

The timer object could be deleted from its Notify(), so don't access it any
more after calling it. Just remember whether it was a one shot timer or not
and reuse this value for the return value of the callback.

Closes #11295.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_8_BRANCH@62333 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

docs/changes.txt

@@ -142,6 +142,9 @@ wxMSW:
   wxBORDER_THEME in a container window.
 - Suppressed spurious character event for decimal key in numeric keypad.
 
+wxGTK:
+
+- Don't access a possibly destroyed timer object from GTK callback (Tim Kosse).
 
 wxMac:
 

src/gtk/timer.cpp

@@ -30,7 +30,8 @@ static gint timeout_callback( gpointer data )
 
     // Don't change the order of anything in this callback!
 
-    if (timer->IsOneShot())
+    const bool oneshot = timer->IsOneShot();
+    if ( oneshot )
     {
         // This sets m_tag to -1
         timer->Stop();
@@ -50,7 +51,7 @@ static gint timeout_callback( gpointer data )
     if (app)
         app->WakeUpIdle();
 
-    if (timer->IsOneShot())
+    if ( oneshot )
         return FALSE;
 
     return TRUE;

src/gtk1/timer.cpp

@@ -29,7 +29,8 @@ static gint timeout_callback( gpointer data )
 
     // Don't change the order of anything in this callback!
 
-    if (timer->IsOneShot())
+    const bool oneshot = timer->IsOneShot();
+    if ( oneshot )
     {
         // This sets m_tag to -1
         timer->Stop();
@@ -45,7 +46,7 @@ static gint timeout_callback( gpointer data )
     // Release lock again.
     gdk_threads_leave();
 
-    if (timer->IsOneShot())
+    if ( oneshot )
         return FALSE;
 
     return TRUE;