Struct lean_sys::lean_object

#[repr(C)]
pub struct lean_object {
    pub m_rc: c_int,
    pub m_cs_sz: u16,
    pub m_other: u8,
    pub m_tag: u8,
}

Lean object header.

The reference counter m_rc field also encodes whether the object is single threaded (> 0), multi threaded (< 0), or reference counting is not needed (== 0). We don’t use reference counting for objects stored in compact regions, or marked as persistent.

For “small” objects stored in compact regions, the field m_cs_sz contains the object size. For “small” objects not stored in compact regions, we use the page information to retrieve its size.

During deallocation and 64-bit machines, the fields m_rc and m_cs_sz store the next object in the deletion TODO list. These two fields together have 48-bits, and this is enough for modern computers. In 32-bit machines, the field m_rc is sufficient.

The field m_other is used to store the number of fields in a constructor object and the element size in a scalar array.

Fields

m_rc: c_int

m_cs_sz: u16

m_other: u8

m_tag: u8

Trait Implementations

impl Clone for lean_object

fn clone(&self) -> lean_object

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for lean_object

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

Formats the value using the given formatter.

impl Copy for lean_object