Docking: crash in UpdateMouseWheel just after loading new docked window layout #4310
Description
Version/Branch of Dear ImGui:
Version: v1.84 WIP (current top of tree hash a11f368)
Branch: docking
Back-end: independant
My Issue/Question:
I got a ImGui crash when using the mouse wheel in the first frame of a newly created window.
The stack trace is (only 0->2 matter for ImGui library):
[PALANTEER] signal 11 'Segmentation fault' received
#0 0x7F79AFB1983C : (null)
#1 imgui.cpp(3895) : ImGui::UpdateMouseWheel()
#2 imgui.cpp(4185) : ImGui::NewFrame()
#3 vwPlatform.cpp(484) : vwPlatform::redraw()
#4 vwPlatform.cpp(404) : vwPlatform::run()
#5 vwPlatform.cpp(279) : bsBootstrap(int, char**)
#6 bsOsLinux.cpp(813) : main
The (obvious) following 1 line patch (the line where the crash occurs) fixes the issue:
imgui.cpp | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/imgui.cpp b/imgui.cpp
index ebd2d104..5136c9f5 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -3905,7 +3905,7 @@ void ImGui::UpdateMouseWheel()
if (wheel_y != 0.0f)
{
StartLockWheelingWindow(window);
- while ((window->Flags & ImGuiWindowFlags_ChildWindow) && ((window->ScrollMax.y == 0.0f) || ((window->Flags & ImGuiWindowFlags_NoScrollWithMouse) && !(window->Flags & ImGuiWindowFlags_NoMouseInputs))))
+ while ((window->Flags & ImGuiWindowFlags_ChildWindow) && ((window->ScrollMax.y == 0.0f) || ((window->Flags & ImGuiWindowFlags_NoScrollWithMouse) && !(window->Flags & ImGuiWindowFlags_NoMouseInputs))) && window->ParentWindow)
window = window->ParentWindow;
if (!(window->Flags & ImGuiWindowFlags_NoScrollWithMouse) && !(window->Flags & ImGuiWindowFlags_NoMouseInputs))
{