(svn r7635) -Fix (r7618, r7621): Guard against recursive deletion. It is possible that when a

 parent window is deleted it deletes its child (always) and in turn, through some
 code the child initiates the deletion of the parent which, if not guarded
 against, deletes the child and so on...

2 files changed, 10 insertions, 3 deletions

diff --git a/misc_gui.c b/misc_gui.c
index 2f2a8d3bf..92ba1b4fa 100644
--- a/misc_gui.c
+++ b/misc_gui.c
@@ -1226,7 +1226,10 @@ static void QueryWndProc(Window *w, WindowEvent *e)
 			break;
 
 		case WE_DESTROY: /* Call callback function (if any) on window close if not yet called */
-			if (!q->calledback && q->proc != NULL) q->proc(w->parent, false);
+			if (!q->calledback && q->proc != NULL) {
+				q->calledback = true;
+				q->proc(w->parent, false);
+			}
 			break;
 	}
 }
diff --git a/window.c b/window.c
index 75da457b5..1a12c7c6b 100644
--- a/window.c
+++ b/window.c
@@ -308,10 +308,13 @@ Window **FindWindowZPosition(const Window *w)
 {
 	Window **wz;
 
-	for (wz = _z_windows;; wz++) {
-		assert(wz < _last_z_window);
+	for (wz = _z_windows; wz != _last_z_window; wz++) {
 		if (*wz == w) return wz;
 	}
+
+	DEBUG(misc, 3, "Window (class %d, number %d) is not open, probably removed by recursive calls",
+		w->window_class, w->window_number);
+	return NULL;
 }
 
 void DeleteWindow(Window *w)
@@ -342,6 +345,7 @@ void DeleteWindow(Window *w)
 	/* Find the window in the z-array, and effectively remove it
 	 * by moving all windows after it one to the left */
 	wz = FindWindowZPosition(w);
+	if (wz == NULL) return;
 	memmove(wz, wz + 1, (byte*)_last_z_window - (byte*)wz);
 	_last_z_window--;
 }