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.

2024-04-28

2749. Treatment of "pointer to void" for relational comparisons

[Accepted as a DR at the November, 2023 meeting.]

(From editorial issue 6173.)

Subclause 7.6.9 [expr.rel] paragraph 4 and paragraph 5 specify:

The result of comparing unequal pointers to objects [ Footnote: ] is defined in terms of a partial order consistent with the following rules: ...

[Note 1: A relational operator applied to unequal function pointers or to unequal pointers to void yields an unspecified result. -- end note]

Comparing pointers to objects that are stored in a variable of type "pointer to void" should be fine.

Proposed resolution (approved by CWG 2023-06-16):

Change in 7.6.9 [expr.rel] paragraph 4 and paragraph 5 as follows:

The result of comparing unequal pointers to objects [ Footnote: ... ] is defined in terms of a partial order consistent with the following rules: ...

[Note 1: A relational operator applied to unequal function pointers or to unequal pointers to void yields an unspecified result. A pointer value of type "pointer to cv void" can point to an object (6.8.4 [basic.compound]). -- end note]