I have a shader that was working on commit 71f2766 which would be DXC commit 0beaa76
It's no longer working after merging DXC d64d34c. It now throws the error in the title when trying to compile, so whatever broke it is somewhere inbetween.
Here's the Godbolt with a repro: https://godbolt.org/z/oKfvE9Mrj