Setting a hard limit on slice size, is this possible?

[Paul Backus]

On Saturday, 7 August 2021 at 14:34:49 UTC, Tejas wrote:
>
> Umm, the ```align array``` solution is flat out wrong,  please 
> ignore it. Most likely a bug in the compiler.
>
> Also, why will the address of the first element of the array 
> ```modulo``` alignment be 0? The address of the array has 
> absolutely nothing to do with the alignment.
>
> You say that the ```align array``` solution has the expected 
> spacing,  but it is default aligned, totally ignoring your 64 
> byte requirement.
>
> Don't use ```x.PTR%ALIGNMENT```
> Use ```(&x[1]-&[2])%ALIGNMENT```
>
> You will get ALIGNMENT*(2 -1)(since you took difference of 2nd 
> and 1st elem)

For the array as a whole to be aligned, not only must the spacing 
between the elements respect the alignment, but starting address 
of the array itself must be a multiple of the alignment. So it is 
correct to check that `x.ptr%ALIGNMENT == 0`.

The issue with `align` attributes being ignored for stack 
variables is apparently a known bug, first reported in 2016: 
https://issues.dlang.org/show_bug.cgi?id=16098

The issue with `align` attributes being ignored by `new` is also 
a known bug, and was also first reported in 2016: 
https://issues.dlang.org/show_bug.cgi?id=16508