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

2025-10-24

3087. Destringizing for raw string literals

The destringizing mechansim omits any treatment of the d-char-sequence of a raw string literal.

Possible resolution:

Change in 15.13 [cpp.pragma.op] paragraph 1 as follows:

A unary operator expression of the form:

  _Pragma ( string-literal )

is processed as follows: The string-literal shall not be a raw string literal (5.13.5 [lex.string]). The string-literal is destringized by deleting the L prefix, if present, deleting the leading and trailing double-quotes, replacing each escape sequence \" by a double-quote, and replacing each escape sequence \\ by a single backslash. The resulting sequence of characters is processed through translation phase 3 to produce preprocessing tokens that are executed as if they were the pp-tokens in a pragma directive. The original four preprocessing tokens in the unary operator expression are removed.

CWG 2025-10-24

There is no consensus to disallow raw string literals in the pragma operator in the C++26 cycle. This core issue is kept open to facilitate further discussion for future C++ releases.