From: stuff overlay maintainer
Subject: Install no-op wx assertion handler at GUI_App::OnInit

OrcaSlicer's CMake recipe builds its bundled wxWidgets with
wxBUILD_DEBUG_LEVEL=0, compiling out all wxASSERT macros (see
deps/wxWidgets/wxWidgets.cmake). The AppImage and AUR builds
take that path, so a number of bad sizer-flag and bitmap-bundle
calls in the upstream source never raise at runtime.

System x11-libs/wxGTK in ::gentoo is built with the upstream
default wxDEBUG_LEVEL=1, so the same calls trigger wxAssert and
wxGUIAppTraits::ShowAssertDialog. The modal dialog runs its own
GTK event loop, during which a periodic OrcaSlicer timer fires
into not-yet-initialised state and segfaults; we never reach the
main window.

Restore the AppImage's effective behaviour at the application
layer by installing a no-op assertion handler at the very start
of GUI_App::OnInit() -- the entry point wxEntry() invokes before
any widget is constructed. This matches upstream's own choice to
ship without runtime wx asserts.

--- a/src/slic3r/GUI/GUI_App.cpp
+++ b/src/slic3r/GUI/GUI_App.cpp
@@ -49,6 +49,7 @@
 #include <wx/sysopt.h>
 #include <wx/richmsgdlg.h>
 #include <wx/log.h>
+#include <wx/debug.h>
 #include <wx/intl.h>

 #include <wx/dialog.h>
@@ -2596,6 +2597,17 @@

 bool GUI_App::OnInit()
 {
+    // stuff overlay: silence wx assertions at runtime to match the
+    // upstream AppImage build, which compiles them out entirely via
+    // -DwxBUILD_DEBUG_LEVEL=0 in deps/wxWidgets/wxWidgets.cmake.
+    // System x11-libs/wxGTK is built with wxDEBUG_LEVEL=1, so the
+    // same upstream sizer/widget calls would otherwise raise modal
+    // assertion dialogs that block startup and segfault on the
+    // re-entrant timer event.
+    wxSetAssertHandler([](const wxString&, int, const wxString&,
+                          const wxString&, const wxString&) {
+    });
+
     try {
         return on_init_inner();
     } catch (const std::exception& e) {