Public Comment Number PC-UK0158 ISO/IEC CD 9899 (SC22N2620) Public Comment =========================================== Date: 1998-02-25 Author: N.M Maclaren Author Affiliation: Self Postal Address: University of Cambridge, Computer Laboratory, New Museums Site, Pembroke Street, Cambridge CB3 3QG, United Kingdom E-mail Address: Telephone Number: +44 1223 334761 Fax Number: +44 1223 334679 Number of individual comments: 1 Comment 1. Category: Normative change to existing feature retaining the original intent Committee Draft subsection: F.9 Title: Floating-point exception flags and errno Detailed description: Paragraph 4 is seriously incompatible with the spirit of IEEE 754 and the wording of LIA-1, and actually prevents an implementation from conforming to both C9X and the proposed LIA-2 simultaneously, for those functions that are not specifically mentioned in this annex. I suggest changing its wording to: 4 The invalid exception will be raised whenever errno is set to EDOM. Subsequent subclauses of this annex specify other circumstances when the invalid or divide-by-zero exceptions are required to be raised. There is also a possible ambiguity in paragraphs 5 and 6, and a problem caused by cases where the implementation may define extra range errors as permitted by 7.7.1 Treatment of error conditions paragraph 2 (e.g. cos(1.0e50)), that is a nasty conflict with LIA-2. It should be closed by adding the following: 6a Whenever errno is set to ERANGE, at least one of the invalid, divide-by-zero, overflow or underflow exceptions shall be raised.