Line comments versus line splicing

Here's a thing I was pondering the other day about lexing.

Suppose you have a language containing two moderately common lexical features: a comment mechanism in which comments are newline-terminated (C++/C99 style //, shell #), and a line-splicing mechanism in which a backslash at the end of a line causes the next line to be glued on to it as if they were one long line. How should these interact?

( some ponderings and a suggestion )