This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21 Core Issues List revision 118f. See http://www.open-std.org/jtc1/sc22/wg21/ for the official list.

2025-11-07

3106. Redundant exclusion of (non-existent) UCNs in r-char-sequences

(From submission #785.)

Subclause 5.3.2 [lex.universal.char] paragraph 1 specifically excludes universal-character-names within r-char-sequences, but universal-character-names are never formed there.

Proposed resolution (approved by CWG 2025-11-04):

Change in 5.3.2 [lex.universal.char] paragraph 1 as follows:

... If a universal-character-name outside the c-char-sequence, or s-char-sequence , or r-char-sequence of a character-literal or string-literal (in either case, including within a user-defined-literal) corresponds to a control character or to a character in the basic character set, the program is ill-formed. ...