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Section: 19.18.3 [execpol.type] Status: NAD Submitter: United States Opened: 2017-02-03 Last modified: 2017-07-16
Priority: Not Prioritized
View all issues with NAD status.
Discussion:Addresses US 14
A user specialization of any is_execution_policy should produce an ill-formed program, not merely one whose behavior is unspecified. See also the related comment re [meta.type.synop] (20.15.2). (US 10)
Proposed change: Reword the paragraph as follows:
See also LWG 2871.
Unless otherwise specified, a program that adds specializations for is_execution_policy is ill-formed; no diagnostic required.
[2017-03-03, Kona Friday AM]
Jonathan: This breaks all known implementations of parallel algorithms, since they use custom execution policies.
Alisdair to check with SG1 to see if that's what they meant.
[2017-07 Toronto Thurs Issue Prioritization]
NAD; what the standard says is that this is "undefined", not "unspecified".