Cherry-picked from Qt upstream (commit e488f852fa18c2afc2842a88eff8f66ad4105a45).
Original patch source:
https://download.qt.io/official_releases/qt/6.11/CVE-2026-6210-qtsvg-6.11.diff
Fix: Test types of nodes before downcasting them. A bad cast in
QSvgMarker::drawHelper led to endless recursion resulting in a heap
overflow. While fixing that, another similar case was also fixed.
Gnulib generates lib/sched.h which wraps the system sched.h via
#include_next, but the #if @HAVE_SCHED_H@ guard evaluates to 0 during
cross-compilation, preventing sched_param typedef from being visible.
Adding ac_cv_header_sched_h=yes fixes the guard.
fstools.mk: Use canonical local/sources/ paths for installer and redoxfs
cargo install --path. The recipes/ symlink chain caused cargo to resolve
path dependencies (../libredox, ../redoxfs, ../syscall) relative to the
recipe directory instead of the canonical source location, breaking
the host build.
bison: Add cross-compilation cache variables for POSIX spawn support.
Gnulib's configure couldn't detect the system spawn.h during cross-compile,
causing generated lib/spawn.h to omit #include_next, leaving
POSIX_SPAWN_* constants undefined.
vasilito