0000605: fmod(NaN,0), fmod(infinity,NAN), fmod(0,NaN) are ambiguous

ID	Project	Category	View Status	Date Submitted	Last Update

0000605	1003.1(2008)/Issue 7	System Interfaces	public	2012-09-12 20:37	2019-06-10 08:55

Reporter	tydeman	Assigned To	ajosey
Priority	normal	Severity	Comment	Type	Clarification Requested
Status	Closed	Resolution	Accepted As Marked

Name	Fred J. Tydeman
Organization	Tydeman Consulting
User Reference	XSH System Interfaces
Section	fmod()
Page Number	870
Line Number	28887
Interp Status	Approved
Final Accepted Text	see 0000605:0001367


Summary	0000605: fmod(NaN,0), fmod(infinity,NAN), fmod(0,NaN) are ambiguous
Description	It is not clear if line 29304: If x or y is NaN, a NaN shall be returned. overrides line 29305: If y is zero, ... and line 29306 If x is infinite, ... and line 29307 If x is +/-0 ... for the cases fmod(NaN,0), fmod(infinity,NAN) and fmod(0,NaN). C11 in F.10 has (paragraph 11): Functions with a NaN argument return a NaN result and raise no ﬂoating-point exception, except where stated otherwise. F.10.7.1 has: fmod(±0, y) returns ±0 for y not zero. and fmod(x, y) returns a NaN and raises the ‘‘invalid’’ ﬂoating-point exception for x inﬁnite or y zero (and neither is a NaN). So, the 1st case does not mention other argument being a NaN, and the 2nd case does mention other argument being a NaN, As far as I recall, all implementations return NaN if any argument is a NaN, and do not indicate any kind of error.
Desired Action	In lines 29305-7, add words about other argument not being a NaN.
Tags	tc2-2008

eblake 2012-09-19 15:44 manager bugnote:0001367 Last edited: 2012-09-19 15:56	Interpretation response ------------------------ The standard is unclear on this issue, and no conformance distinction can be made between alternative implementations based on this. This is being referred to the sponsor. Rationale: ------------- It was ambiguous whether a domain error shall occur, the suggested change matches existing implementation of no domain error. Notes to the Editor (not part of this interpretation): ------------------------------------------------------- [These edits are based on the text in Issue 7; although the original Description and Desired Action were based off of a draft for TC1 with other changes in neighboring text already incorporated.] On page 870 line 28887, change: If x or y is NaN, a NaN shall be returned. to: If x or y is NaN, a NaN shall be returned, and none of the conditions below shall be considered.

ajosey 2013-03-29 08:06 manager bugnote:0001524	Interpretation Proposed 29 Mar 2013

ajosey 2013-05-03 12:18 manager bugnote:0001571	Interpretation approved 3 May 2013

Date Modified	Username	Field	Change
2012-09-12 20:37	tydeman	New Issue
2012-09-12 20:37	tydeman	Status	New => Under Review
2012-09-12 20:37	tydeman	Assigned To	=> ajosey
2012-09-12 20:37	tydeman	Name	=> Fred J. Tydeman
2012-09-12 20:37	tydeman	Organization	=> Tydeman Consulting
2012-09-12 20:37	tydeman	User Reference	=> XSH System Interfaces
2012-09-12 20:37	tydeman	Section	=> fmod()
2012-09-12 20:37	tydeman	Page Number	=> 876
2012-09-12 20:37	tydeman	Line Number	=> 29305-7
2012-09-19 15:44	eblake	Note Added: 0001367
2012-09-19 15:48	eblake	Note Edited: 0001367
2012-09-19 15:52	eblake	Page Number	876 => 870
2012-09-19 15:52	eblake	Line Number	29305-7 => 28887
2012-09-19 15:52	eblake	Interp Status	=> Pending
2012-09-19 15:52	eblake	Final Accepted Text	=> see 0000605:0001367
2012-09-19 15:52	eblake	Status	Under Review => Interpretation Required
2012-09-19 15:52	eblake	Resolution	Open => Accepted As Marked
2012-09-19 15:52	eblake	Tag Attached: tc2-2008
2012-09-19 15:53	eblake	Relationship added	related to 0000320
2012-09-19 15:55	eblake	Note Edited: 0001367
2012-09-19 15:56	eblake	Note Edited: 0001367
2013-03-29 08:06	ajosey	Interp Status	Pending => Proposed
2013-03-29 08:06	ajosey	Note Added: 0001524
2013-05-03 12:18	ajosey	Interp Status	Proposed => Approved
2013-05-03 12:18	ajosey	Note Added: 0001571
2019-06-10 08:55	agadmin	Status	Interpretation Required => Closed