The HAL types and isolation work on master 2.10, changes how C/C++ components register and access pins and params: opaque refs with hal_get_*/hal_set_* accessors instead of direct volatile pointer dereference. The old API still builds (deprecations, not removals), so this is a migration window, if you need clarification please post here or better on
github.com/LinuxCNC/linuxcnc/discussions/4393
