Struct GcPtr 

pub struct GcPtr<T> { /* private fields */ }

A pointer to a GC-managed object of type T.

The object is laid out in memory as:

[GcHeader (8 bytes)][T data (size bytes)]
                     ^--- GcPtr points here

GcPtr is Copy — no refcount manipulation. The GC is solely responsible for determining liveness and reclaiming memory.

Implementations

impl<T> GcPtr<T>

pub unsafe fn from_raw(ptr: *mut T) -> Self

Create a GcPtr from a raw pointer.

Safety

The pointer must point to a valid T preceded by a GcHeader at ptr - 8.

pub fn as_ptr(self) -> *mut T

Get the raw pointer to T.

pub fn as_usize(self) -> usize

Get the raw pointer as usize (for NaN-boxing payload).

pub fn header(self) -> &'static GcHeader

Get a reference to the GcHeader preceding this object.

pub unsafe fn header_mut(self) -> &'static mut GcHeader

Get a mutable reference to the GcHeader preceding this object.

Safety

Caller must ensure exclusive access to the header.

pub unsafe fn deref_gc(self) -> &'static T

Dereference to get a reference to the managed object.

Safety

The object must still be alive (not collected).

pub unsafe fn deref_gc_mut(self) -> &'static mut T

Dereference to get a mutable reference to the managed object.

Safety

The object must still be alive and caller must have exclusive access.

pub fn with_mark_bit(self) -> Self

Set the inline mark bit (x86-64: use LAM if available, else no-op).

pub fn clear_mark_bit(self) -> Self

Clear the inline mark bit (x86-64: use LAM if available, else no-op).

pub fn has_mark_bit(self) -> bool

Check whether the inline mark bit is set (x86-64: use LAM if available).

pub fn is_marked(self) -> bool

Check the mark state, combining inline pointer bits with the GcHeader side table for a definitive answer on any platform.

Returns true if either the inline mark bit is set (on HW-masking platforms) or the GcHeader color is Gray/Black.

pub fn raw_ptr(self) -> *mut T

Strip all metadata bits from the pointer, returning the raw address.

Uses the detected masking mode to apply the correct mask.

pub fn as_untyped(self) -> *mut u8

Convert to an untyped pointer for use in the root set / marker.

pub unsafe fn from_untyped(ptr: *mut u8) -> Self

Create from an untyped pointer.

Safety

The pointer must actually point to a valid T with GcHeader prefix.

Trait Implementations

impl<T> Clone for GcPtr<T>

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: Debug> Debug for GcPtr<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T> Pointer for GcPtr<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T> Copy for GcPtr<T>