Segmentation fault in DMD - how to debug?

[Paul Backus]

On Wednesday, 28 September 2022 at 23:15:42 UTC, Andrey Zherikov 
wrote:
> On Wednesday, 28 September 2022 at 23:07:34 UTC, Nicholas 
> Wilson wrote:
>> This seems to stem from use of `__traits(getPointerBitmap, 
>> T)`, with a `T` that is not handled properly. If you can get a 
>> reduced test case that will make things much easier. 
>> `dustmite` (which should come with `dmd`, is useful for 
>> automatic reduction, otherwise if you have few uses of 
>> `__traits(getPointerBitmap, T)`, it might be easier to 
>> synthesise an example that crashes the compiler.
>
> I don't use `getPointerBitmap` in my code:
> ```
> $ grep -r --include=*.d getPointerBitmap
> $
> ```

It's used in druntime, by `RTInfo`:

https://github.com/dlang/druntime/blob/v2.100.2/src/object.d#L3695-L3702