cannot build as library in release mode

[WebFreak001]

When cloning mir-ion, checking out 2.0.16 and running dub build --build=release --config=library the following happens:

dub build --build=release --config=library
Performing "release" build using /usr/bin/dmd for x86_64.
mir-ion 2.0.16: building configuration "library"...
source/mir/ion/internal/data_holder.d(178,24): Error: null dereference in function _D3mir5deser4text__T19IonTextDeserializerTSQBp3ser3ion__T13IonSerializerVki32768VAAyanVbi1ZQBiZQCx5__barFNbZv
source/mir/ion/internal/data_holder.d(145,9): Error: null dereference in function _D3mir5deser4text__T19IonTextDeserializerTSQBp3ser3ion__T13IonSerializerVki32768VAAyanVbi1ZQBiZQCx5__barFNbZv
Error: null dereference in function _D3mir5deser4text__T19IonTextDeserializerTSQBp3ser3ion__T13IonSerializerVki32768VAAyanVbi1ZQBiZQCx5__barFNbZv
Error: null dereference in function _D3mir5deser4text__T19IonTextDeserializerTSQBp3ser3ion__T13IonSerializerVki32768VAAyanVbi1ZQBiZQCx5__barFNbZv
Error: null dereference in function _D3mir5deser4text__T19IonTextDeserializerTSQBp3ser3ion__T13IonSerializerVki32768VAAyanVbi1ZQBiZQCx5__barFNbZv
source/mir/ion/internal/data_holder.d(155,17): Error: null dereference in function _D3mir5deser4text__T19IonTextDeserializerTSQBp3ser3ion__T13IonSerializerVki32768VAAyanVbi1ZQBiZQCx5__barFNbZv
source/mir/ion/internal/data_holder.d(154,55): Error: null dereference in function _D3mir5deser4text__T19IonTextDeserializerTSQBp3ser3ion__T13IonSerializerVki32768VAAyanVbi1ZQBiZQCx5__barFNbZv
source/mir/ion/internal/data_holder.d(154,28): Error: null dereference in function _D3mir5deser4text__T19IonTextDeserializerTSQBp3ser3ion__T13IonSerializerVki32768VAAyanVbi1ZQBiZQCx5__barFNbZv
source/mir/ion/internal/data_holder.d(152,42): Error: null dereference in function _D3mir5deser4text__T19IonTextDeserializerTSQBp3ser3ion__T13IonSerializerVki32768VAAyanVbi1ZQBiZQCx5__barFNbZv
source/mir/ion/internal/data_holder.d(152,13): Error: null dereference in function _D3mir5deser4text__T19IonTextDeserializerTSQBp3ser3ion__T13IonSerializerVki32768VAAyanVbi1ZQBiZQCx5__barFNbZv
Error: null dereference in function _D3mir5deser4text__T19IonTextDeserializerTSQBp3ser3ion__T13IonSerializerVki32768VAAyanVbi1ZQBiZQCx5__barFNbZv
/usr/bin/dmd failed with exit code 1.