As a simple example, consider a package that uses cgo to call C.sin.
The following code will be generated by cgo:

	// compiled by gc

	//go:cgo_ldflag "-lm"

	type _Ctype_double float64

	//go:cgo_import_static _cgo_gcc_Cfunc_sin
	//go:linkname __cgo_gcc_Cfunc_sin _cgo_gcc_Cfunc_sin
	var __cgo_gcc_Cfunc_sin byte
	var _cgo_gcc_Cfunc_sin = unsafe.Pointer(&__cgo_gcc_Cfunc_sin)