During MLIR translation to LLVMIR if an inlineable call has an UnkownLoc we get this error message:
inlinable function call in a function with debug info must have a !dbg location call void @callee()
There is code that checks for this case and strips debug information to avoid this situation. I'm expanding this code to handle the case where an debug location points at a UnknownLoc. For example, a NamedLoc whose child location is an UnknownLoc.