Function guile_sys::__gmp_set_memory_functions

pub unsafe extern "C" fn __gmp_set_memory_functions(
    arg1: Option<unsafe extern "C" fn(arg1: usize) -> *mut c_void>, 
    arg2: Option<unsafe extern "C" fn(arg1: *mut c_void, arg2: usize, arg3: usize) -> *mut c_void>, 
    arg3: Option<unsafe extern "C" fn(arg1: *mut c_void, arg2: usize)>
)