This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21 Core Issues List revision 120a. See http://www.open-std.org/jtc1/sc22/wg21/ for the official list.

2026-06-10

3194. Lexing of <=>

(From submission #910.)

Consider:

  #include <=>

Is this lexed as a header-name or a punctuator?

Suggested resolution:

Change in 5.5 [lex.pptoken] bullet 5.4.1 as follows:

• ...
• Otherwise, the next preprocessing token is the longest sequence of characters that could constitute a preprocessing token, even if that would cause further lexical analysis to fail, except that
  • a string-literal or preprocessing-op-or-punc preprocessing token is never formed when a header-name preprocessing token can be formed, and
  • ...