Bug 15750

Summary:	Various functions raise FE_INEXACT when the results are exact and representable
Product:	glibc	Reporter:	Jeremy <gcc.hall>
Component:	math	Assignee:	Not yet assigned to anyone <unassigned>
Status:	RESOLVED INVALID
Severity:	normal	CC:	gcc.hall
Priority:	P2	Flags:	fweimer: security-
Version:	2.16
Target Milestone:	---
Host:		Target:
Build:		Last reconfirmed:

Description Jeremy 2013-07-17 13:02:43 UTC

Examples are log10(100), cbrt(27), exp10(2), log2(2), pow(4.0, 0.5)

These all return the correct exact value, but FE_INEXACT is raised.

Comment 1 Joseph Myers 2013-07-17 13:27:44 UTC

None of these are functions (such as fma or sqrt) for which Annex F specifies correct "inexact" exceptions, and as such correctly raising or not raising "inexact" for them is outside the goals for correctness of results that I described at <http://sourceware.org/ml/libc-alpha/2013-05/msg00132.html>.

If you find bugs that are bugs according to the goals as described there, please file separate bugs in Bugzilla for each function, and each distinct issue (missing exceptions / spurious exceptions / inaccurate return value / missing errno / incorrect errno), after checking the bug isn't already filed; omnibus bug reports about "various functions" should be avoided, as liable to lead to a long time when a bug is partly fixed, a state Bugzilla is not good at tracking.  (A single bug can cover all of the float, double and long double versions of a function, if they appear to share an issue.)