Struct GcState 

pub struct GcState {
    pub generations: [GcGeneration; 3],
    pub permanent: GcGeneration,
    pub enabled: AtomicBool,
    pub debug: AtomicU32,
    pub garbage: PyMutex<Vec<PyObjectRef>>,
    pub callbacks: PyMutex<Vec<PyObjectRef>>,
    /* private fields */
}

Global GC state

Fields

generations: [GcGeneration; 3]

3 generations (0 = youngest, 2 = oldest)

permanent: GcGeneration

Permanent generation (frozen objects)

enabled: AtomicBool

GC enabled flag

debug: AtomicU32

Debug flags

garbage: PyMutex<Vec<PyObjectRef>>

gc.garbage list (uncollectable objects with del)

callbacks: PyMutex<Vec<PyObjectRef>>

gc.callbacks list

Implementations

impl GcState

pub fn new() -> Self

pub fn is_enabled(&self) -> bool

Check if GC is enabled

pub fn enable(&self)

Enable GC

pub fn disable(&self)

Disable GC

pub fn get_debug(&self) -> GcDebugFlags

Get debug flags

pub fn set_debug(&self, flags: GcDebugFlags)

Set debug flags

pub fn get_threshold(&self) -> (u32, u32, u32)

Get thresholds for all generations

pub fn set_threshold(&self, t0: u32, t1: Option<u32>, t2: Option<u32>)

Set thresholds

pub fn get_count(&self) -> (usize, usize, usize)

Get counts for all generations

pub fn get_stats(&self) -> [GcStats; 3]

Get statistics for all generations

pub unsafe fn track_object(&self, obj: NonNull<PyObject>)

Track a new object (add to gen0). O(1) — intrusive linked list push_front, no hashing.

Safety

obj must be a valid pointer to a PyObject

pub unsafe fn untrack_object(&self, obj: NonNull<PyObject>)

Untrack an object (remove from GC lists). O(1) — intrusive linked list remove by node pointer.

Safety

obj must be a valid pointer to a PyObject that is currently tracked. The object’s memory must still be valid (pointers are read).

pub fn get_objects(&self, generation: Option<i32>) -> Vec<PyObjectRef>

Get tracked objects (for gc.get_objects) If generation is None, returns all tracked objects. If generation is Some(n), returns objects in generation n only.

pub fn maybe_collect(&self) -> bool

Check if automatic GC should run and run it if needed. Called after object allocation. Returns true if GC was run, false otherwise.

pub fn collect(&self, generation: usize) -> CollectResult

Perform garbage collection on the given generation

pub fn collect_force(&self, generation: usize) -> CollectResult

Force collection even if GC is disabled (for manual gc.collect() calls)

pub fn get_freeze_count(&self) -> usize

Get count of frozen objects

pub fn freeze(&self)

Freeze all tracked objects (move to permanent generation). Lock order: generation_lists[i] → permanent_list (consistent with unfreeze).

pub fn unfreeze(&self)

Unfreeze all objects (move from permanent to gen2). Lock order: generation_lists[2] → permanent_list (consistent with freeze).

Trait Implementations

impl Default for GcState

fn default() -> Self

Returns the “default value” for a type.