func golang.org/x/sys/unix.MunmapPtr

one use

	golang.org/x/sys/unix (current package)
		syscall_unix.go#L162: func MunmapPtr(addr unsafe.Pointer, length uintptr) (err error) {

The pages are generated with Golds v0.7.6. (GOOS=linux GOARCH=amd64)