Suggesting ways to handle invalid addresses in Golang.

invalid_address.go

package main

import (
	"errors"
	"log"
	"unsafe"
)

func foo1() (err error) {
	defer func() {
		r := recover()
		log.Println("Recovered:", r) //
		if r != nil {
			err = r.(error)
		}
	}()
	panic(errors.New("I'm a recoverable panic! Yay"))
	return err
}

func foo2() (err error) {
	defer func() {
		r := recover()
		if r != nil {
			log.Println("Recovered:", r) //
			err = r.(error)
		}
	}()

	// purposely accessing the nil address.
	nilptr := (*int)(unsafe.Pointer(uintptr(0x0)))
	v := *nilptr
	log.Println(nilptr, v)

	// this is an invalid address.
	someAddr := (*uintptr)(unsafe.Pointer(uintptr(0xdd7ae08)))
	log.Println(someAddr)

	// purposely accessing the fault address.
	// this will cause:
	// ```
	// unexpected fault address 0xdd7ae08
	// fatal error: fault
	// ```
	// a fatal error is different from a panic.
	// unlike a panic a fatal error just terminates the entire program and can't be handled any way.
	val := *someAddr
	log.Println(val)

	return err
}

func main() {
	log.Println("foo1():")
	log.Println(foo1())
	log.Println("foo1() returned.")

	log.Println("foo2():")
	log.Println(foo2())
	log.Println("foo2() returned.")

}