While debugging, I saw a log line of:
> Failed to resolve SDK path: Error while searching for SDK (XcodeSDK ''): Unrecognized SDK type:
Looking into how this might happen, it seems `ResolveSDKPathFromDebugInfo` appears to
(implicitly) assume there's at least one compile unit. This change adds a precondition
to return a meaningful error when there are no compile units.
Original: https://github.com/llvm/llvm-project/pull/146062
a447fc63f9