Function mspace_realloc 

pub unsafe extern "C" fn mspace_realloc(
    msp: *mut c_void,
    mem: *mut c_void,
    newsize: usize,
) -> *mut c_void

mspace_realloc behaves as realloc, but operates within the given space.

If compiled with FOOTERS==1, mspace_realloc is not actually needed. realloc may be called instead of mspace_realloc because realloced chunks from any space are handled by their originating spaces.