On Saturday, 19 November 2022 at 14:07:59 UTC, Nick Treleaven wrote:
Hi,
The following seems like a bug to me (reduced code, FILE* changed to int*):
```d
@safe:

struct LockedFile
{
    private int* fps;

    auto fp() return scope => fps;
}

void main()
{
    int* p;
    {
        auto lf = LockedFile(new int);
        p = lf.fp;
    }
    assert(p != null); // address escaped
}
```
There's no error with -dip1000.
I'll file this unless I overlooked something.

I think this is intended behavior, because you *do* get an error if you replace `new int` with a pointer to a stack variable; e.g.,

    int local;
    auto lf = LockedFile(&local);

The `return scope` qualifier on the method does *not* mean "the return value of this method is `scope`". It means "this method may return one of this object's pointers, but does not allow them to escape anywhere else." In other words, it lets the compiler determine that the return value of `lf.fp` has *the same* lifetime as `lf` itself.

Since, in your example, `lf` has global lifetime, the compiler deduces that `lf.fp` also has global lifetime, and therefore there is nothing wrong with assigning it to `p`.

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