fn reallocAdvanced(self: Allocator, old_mem: anytype, new_n: usize, return_address: usize) t: {
    const Slice = @typeInfo(@TypeOf(old_mem)).Pointer;
    break :t Error![]align(Slice.alignment) Slice.child;
}

Parameters

self: Allocator,
old_mem: anytype,
new_n: usize,
return_address: usize,