Function __builtin_object_size [src]

Prototype

pub inline fn __builtin_object_size(ptr: ?*const anyopaque, ty: c_int) usize

Parameters

ptr: ?*const anyopaquety: c_int

Source

  pub inline fn __builtin_object_size(ptr: ?*const anyopaque, ty: c_int) usize {
    _ = ptr;
    // clang semantics match gcc's: https://gcc.gnu.org/onlinedocs/gcc/Object-Size-Checking.html
    // If it is not possible to determine which objects ptr points to at compile time,
    // __builtin_object_size should return (size_t) -1 for type 0 or 1 and (size_t) 0
    // for type 2 or 3.
    if (ty == 0 or ty == 1) return @as(usize, @bitCast(-@as(isize, 1)));
    if (ty == 2 or ty == 3) return 0;
    unreachable;
}  