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digitalmars.D.bugs - [Issue 1637] New: regression: new unittest failure in std/math2.d, odd cosh() behavior

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=1637

           Summary: regression: new unittest failure in std/math2.d, odd
                    cosh() behavior
           Product: D
           Version: 2.007
          Platform: PC
        OS/Version: Windows
            Status: NEW
          Keywords: wrong-code
          Severity: regression
          Priority: P2
         Component: Phobos
        AssignedTo: bugzilla digitalmars.com
        ReportedBy: braddr puremagic.com


From std/math2.d:

616 real coth(real x)
617 {
618         return 1 / tanh(x);
619 }
620 
621 unittest
622 {
623         assert(feq(coth(1), cosh(1) / sinh(1)));
624 }

This test fails with dmd 2.007 and doesn't with dmd 2.006 (using the 2.006
phobos code, 2.007's phobos needs dmd 2.007 to build, but there's no changes to
the math code in phobos between 2.006 and 7).

My attempts to reduce the failure so far have been interesting.  Adding
printf's of each of the function results shows that adding a writeln for cosh
is enough to make the error go away.  One write of cosh(1) shows inf as the
result.  Two writes of cosh(1): first is inf, second is 1.54308.

I tried pulling the test code out to it's own tiny .d file and it doesn't fail.
 It always prints 1.54308 for cosh(1).


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Nov 04 2007
next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=1637





------- Comment #1 from braddr puremagic.com  2008-03-08 18:08 -------
Created an attachment (id=233)
 --> (http://d.puremagic.com/issues/attachment.cgi?id=233&action=view)
stand alone test case

I figured out how to cut this test case out of the full library into a single
.d file.  Change essentially _anything_ and the error goes away.

$ dmd -unittest bug1637.d && ./bug1637
Error: AssertError Failure bug1637.d(89) 


--
Mar 08 2008
prev sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=1637


bugzilla digitalmars.com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |WORKSFORME




------- Comment #2 from bugzilla digitalmars.com  2008-08-28 03:31 -------
Irrelevant for D 2.0 which has dropped std.math2.

Works in D 1.0 1.034.


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Aug 28 2008