This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21 Core Issues List revision 116a. See http://www.open-std.org/jtc1/sc22/wg21/ for the official list.

2024-12-19


1354. Destructor exceptions for temporaries in noexcept expressions

Section: 7.6.2.7  [expr.unary.noexcept]     Status: CD3     Submitter: Sebastian Redl     Date: 2011-08-16

[Moved to DR at the October, 2012 meeting.]

The result of the noexcept operator does not consider possible exceptions thrown by the destructors for temporaries created in the operand expression.

Proposed resolution (February, 2012):

  1. Change 6.9.1 [intro.execution] paragraph 10 as follows:

  2. A full-expression is an expression that is not a subexpression of another expression. [Note: in some contexts such as unevaluated operands, a syntactic subexpression is considered a full-expression (Clause 7 [expr]). —end note] If a language construct...
  3. Change Clause 7 [expr] paragraph 7 as follows:

  4. ...An unevaluated operand is not evaluated. An unevaluated operand is considered a full-expression. [Note:...

[Drafting note: This uniformly handles sizeof(A()), noexcept(A()), typeid(A()), and decltype(A()) with regard to the semantic requirements on ~A (accessible and not deleted), which might be checked via SFINAE. A programmer can use decltype(new A) to avoid considering the destructor. If this is undesired, an alternative change just addresses the noexecept issue:]

[Editing note: all the occurrences of “potentially evaluated” in 7.6.2.7 [expr.unary.noexcept] paragraph 3 should be hyphenated.]