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  • #8780

Closed
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Opened Feb 13, 2014 by lennart@augustsson.net@trac-lennart

abs for IEEE floating point is slightly wrong.

Evaluating abs(-0) gives the answer -0. This unexpected since it breaks invariants like 1/(abs x) >= 0. So abs(-0) should be 0. This is also the norm for other languages.

Together with this change, signum should also be changed so signum(-0) is -0. This maintains the invariant abs x * signum x == x.

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Version 7.6.3
Type Bug
TypeOfFailure OtherFailure
Priority low
Resolution Unresolved
Component Compiler
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Reference: ghc/ghc#8780