Bug 8250 - Math.Pow() returns incorrect results on ARM build
Summary: Math.Pow() returns incorrect results on ARM build
Status: RESOLVED DUPLICATE of bug 7938
Alias: None
Product: Runtime
Classification: Mono
Component: JIT ()
Version: unspecified
Hardware: Other Linux
: --- normal
Target Milestone: ---
Assignee: Bugzilla
URL:
Depends on:
Blocks:
 
Reported: 2012-11-06 16:45 UTC by XamarinBugzilla.20.jwman
Modified: 2012-11-07 11:07 UTC (History)
3 users (show)

Tags:
Is this bug a regression?: ---
Last known good build:


Attachments
Simple test program that ouputs results of calling Math.Pow (615 bytes, text/x-csharp)
2012-11-06 16:45 UTC, XamarinBugzilla.20.jwman
Details


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Status:
RESOLVED DUPLICATE of bug 7938

Description XamarinBugzilla.20.jwman 2012-11-06 16:45:08 UTC
Created attachment 2872 [details]
Simple test program that ouputs results of calling Math.Pow

Mono Version 2.10.8.1ubuntu2.1
Ubuntu 12.04 
Running on BeagleBone platform.

Calling Math.Pow() returns incorrect results, like this:

Math.Pow(10, -5) results.  Expected: 1E-05  Actual: 0.00891799479722977
Math.Pow(10, 5) results.  Expected: 100000  Actual: 0.257413864135742
Math.Pow(2, 4) results.  Expected: 16  Actual: 0.263913869857788
Math.Pow(2, 8) results.  Expected: 256  Actual: 1

This works as expected on the x86 version 2.10.8.1 (Debian 2.10.8.1-1~dhx1~lucid1).
Comment 1 Zoltan Varga 2012-11-07 00:21:31 UTC
Probably a dup of:
https://bugzilla.xamarin.com/show_bug.cgi?id=7938
Comment 2 XamarinBugzilla.20.jwman 2012-11-07 00:39:24 UTC
Ah.  Yes, it is in fact using hardfp.  Didn't know that caused issues with mono.

I'm sure that's the cause.
Comment 3 Zoltan Varga 2012-11-07 11:07:46 UTC

*** This bug has been marked as a duplicate of bug 7938 ***