When` SmallVector<char>` is used as a backing storage, it can't be assumed to end with a \x0. When creating a `StringRef` from it, pass the length explicitly. This was detected by address sanitizer.
When` SmallVector<char>` is used as a backing storage, it can't be assumed to end with a \x0. When creating a `StringRef` from it, pass the length explicitly. This was detected by address sanitizer.