implement the full semantics of the host linker, so the kinds of
objects that can be linked directly into the binary is limited (other
code can only be used as a dynamic library). On the other hand, when
using internal linking, cmd/link can generate Go binaries by itself.

In order to allow linking arbitrary object files without requiring
dynamic libraries, cgo supports an "external" linking mode too. In

world, because the Go garbage collector is unaware of the memory
allocated by C.  The most important consideration is not to
constrain future implementations, so the rule is that Go code can
hand a Go pointer to C code but must separately arrange for
Go to hang on to a reference to the pointer until C is done with it.
*/
package gmp

/*
#cgo LDFLAGS: -lgmp
#include <gmp.h>
#include <stdlib.h>