Function mi_calloc_aligned_at 

pub unsafe extern "C" fn mi_calloc_aligned_at(
    count: usize,
    size: usize,
    alignment: usize,
    offset: usize,
) -> *mut c_void

Allocate size * count bytes aligned by alignment at a specified offset, zero-initialized.

This is a calloc equivalent of mi_malloc_aligned_at.