Returning dynamic array from the function

[sclytrack]

On Wednesday, 17 October 2012 at 19:22:05 UTC, Simen Kjaeraas 
wrote:
> On 2012-10-17, 21:17, m0rph wrote:
>
>> I tryed to learn how arrays works and found another strange 
>> thing:
>>
>> import std.stdio;
>>
>> int[] create()
>> {
>> 	int[5] a1 = [ 10, 20, 30, 40, 50 ];
>> 	int[] b1 = a1;
>> 	writeln("b1: ", b1);
>> 	return b1;
>> }
>>
>> void main()
>> {
>> 	int[] a2 = create();
>> 	writeln("a2: ", a2);
>> }
>>
>> Result of execution:
>> b1: [10, 20, 30, 40, 50]
>> a2: [-142625792, 32767, 4358059, 0, 5]
>>
>> Please explain what's wrong with this code? Why variable a2 
>> contains crap? Is this another dmd/druntime bug or I missed 
>> something?
>
> b1 points to the exact same data as does a1. This data is stack-
> allocated, and thus a2 points to an overwritten stack frame.


It doesn't give an error when marking the function with safe.

@safe
int[] create()
{
}