Safe mode in D?

[DDD]

On Thursday, 17 October 2013 at 23:08:13 UTC, Ali Çehreli wrote:
> On 10/17/2013 03:56 PM, DDD wrote:
>> Hi I heard that you can pass a command line argument to make D 
>> safe.
>> Like 0 chance of memory corruption and such. I tried looking 
>> here
>> http://dlang.org/dmd-linux.html but I couldn't figure it out. 
>> If it
>> matters I'm on windows using the latest until a new version 
>> came out
>> ~3weeks ago
>
> An example to complement Adam D. Ruppe's answer:
>
> /* @system is the default */
> @system void can_do_anything()
> {
>     int a;
>     int * p = &a;
> }
>
> /* Must be @trusted to be able to call function that are safe 
> but not marked
>  * as such. */
> @trusted void bridge_between_safe_and_actually_safe()
> {
>     safe_but_not_marked_as_such();
> }
>
> @safe void safeD_function()
> {
>     int a;
>     // CANNOT BE COMPILED:
>     // int * p = &a;
>
>     // Can call @trusted from @safe
>     bridge_between_safe_and_actually_safe();
> }
>
> void safe_but_not_marked_as_such()
> {}
>
> void main()
> {
>     can_do_anything();
>     bridge_between_safe_and_actually_safe();
>     safeD_function();
> }
>
> Ali
>
> P.S. There is also the D.learn newsgroup. ;)


I tried this code and the compiler allowed it (runtime I get 
object.Error: Access Violation). What am I doing wrong?

Thanks I didn't notice

@safe
import std.stdio;
class A {
	int x  = 1;
}
@safe void main() {
	A a;
	a.x=9;
}