std.string.assumeUTF() silently casting mutable to immutable?

[RazvanN]

On Wednesday, 14 February 2024 at 02:13:08 UTC, Forest wrote:
> On Tuesday, 13 February 2024 at 14:05:03 UTC, Johan wrote:
>> On Tuesday, 13 February 2024 at 08:10:20 UTC, Jonathan M Davis 
>> wrote:
>>> 
>>> So, there's definitely a bug here, but it's a dmd bug. Its 
>>> checks for whether it can safely change the constness of the 
>>> return type apparently aren't sophisticated enough to catch 
>>> this case.
>>
>> This is a pretty severe bug.
>
> Thanks, gents.
>
> Reported on the tracker:
>
> https://issues.dlang.org/show_bug.cgi?id=24394

This has already been fixed, you just need to use 
-preview=fixImmutableConv. This was put behind a preview flag as 
it introduces a breaking change.