pub unsafe extern "C" fn free(p: *mut c_void)Expand description
The Objective-C runtime has several methods, usually with “copy” in
their name, whose return value is allocated with C’s malloc and
deallocated with C’s free method.
As such, free is actually also part of the Objective-C runtime.
We expose this instead of using libc::free, to avoid having libc
as a dependency.