This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21 Core Issues List revision 114a. See http://www.open-std.org/jtc1/sc22/wg21/ for the official list.

2024-04-18

37. When is uncaught_exception() true?

Section: 14.6.3  [except.uncaught]     Status: NAD     Submitter: Daveed Vandevoorde     Date: 10 Aug 1998

The term "throw exception" seems to sometimes refer to an expression of the form "throw expr" and sometimes just to the "expr" portion thereof.

As a result it is not quite clear to me whether when "uncaught_exception()" becomes true: before or after the temporary copy of the value of "expr".

Is there a definite consensus about that?

Rationale: The standard is sufficiently clear; the phrase "to be thrown" indicates that the throw itself (which includes the copy to the temporary object) has not yet begun. The footnote in 14.6.2 [except.terminate] paragraph 1 reinforces this ordering.

See also issue 475.