Bug in import(...) on Windows?

[Andrey Zherikov]

On Wednesday, 2 September 2020 at 19:13:47 UTC, Adam D. Ruppe 
wrote:
> On Wednesday, 2 September 2020 at 18:40:55 UTC, Andrey Zherikov 
> wrote:
>> If I provide -Jfoo to dmd, doesn't it mean my consent to use 
>> the contents of directory foo?
>
> Yeah, but dmd has been inconsistent on platforms about if it 
> allows subdirectories. Right now I think it just strips all 
> slashes out so your .\ path there just gets caught in the 
> filter.

I think the issue is here: 
https://github.com/dlang/dmd/blob/master/src/dmd/root/filename.d#L736-L748

Does it makes sense to allow paths in import(file) unless path 
points through parent directory, i.e. 
!buildNormalizedPath(file).startsWith("..")?