ROOT CAUSE: Qt6's auto-generated Wayland wrappers pass NULL proxies
to wl_*_add_listener() during initialization. The generated code stores
wlRegistryBind() return value in m_wl_* member without null check,
then init_listener() calls wl_*_add_listener(m_wl_*, ...) which
page-faults at null+8 (write to proxy->object.implementation).
FIX (kded6): wrapper script renames libqwayland.so to .disabled
before launching kded6.real. QT_QPA_PLATFORM=offscreen alone is not
sufficient — Qt6 still loads wayland plugin despite env var.
FIX (libwayland): null guards in redox.patch for wl_proxy_add_listener,
wl_proxy_get_version, wl_proxy_get_display. Blocked from compilation
by pre-existing relibc conflicts (open_memstream, signalfd_siginfo).
FIX (Qt6 wrappers): regex-based null guard insertion proven in concept.
Blocked by TOML recipe format not supporting backslash escape sequences.
Implementation plan: inject null guards via a separate build step script
rather than inline in recipe.toml.
Add guard-recipes.sh with four modes:
- --verify: check all local/recipes have correct symlinks into recipes/
- --fix: repair broken symlinks (run before builds)
- --save-all: snapshot all recipe.toml into local/recipes/
- --restore: recreate all symlinks from local/recipes/ (run after sync-upstream)
Wired into apply-patches.sh (post-patch) and sync-upstream.sh (post-sync).
This prevents the build system from deleting recipe files during
cargo cook, make distclean, or upstream source refresh.
vasilito