[Issue 21209] scope attribute inference with does not work well with foreach

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=21209

Dennis <dkorpel at live.nl> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |dkorpel at live.nl
           Hardware|x86_64                      |All
                 OS|Linux                       |All

--- Comment #3 from Dennis <dkorpel at live.nl> ---
Worth noting that scope inference also fails on foreach loops of alias
sequences:

```
@safe:
void foo(A...)(A args) 
{
    static int x; x++; // force impure for issue 20150
    foreach(a; args) 
    {
        // gets lowered to unrolled loop with `string a = _param_0;`
    }
}

void main() 
{
    scope string x = "hey";
    foo(x);
}
```

Error: scope variable `x` assigned to non-scope parameter `_param_0` calling
foo!string.foo

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