This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21 Core Issues List revision 112e. See http://www.open-std.org/jtc1/sc22/wg21/ for the official list.
The grammar for #line is inconsistent between 15.7 [cpp.line] paragraph 4:
# line digit-sequence " s-char-sequenceopt " new-line
and 15.7 [cpp.line] paragraph 1:
The string-literal of a #line directive, if present, shall be a character string literal.
The characters comprising the string-literal are not necessarily interpreted for e.g. escape sequences or universal-character-names, so the use of string-literal here is questionable. This directive names a source file, thus it might be better to use header-name (5.8 [lex.header]) instead.