[Bug math/13872] New: powl (10, -LDBL_MAX) raises spurious overflow exception

[Bug math/13872] New: powl (10, -LDBL_MAX) raises spurious overflow exception

[jsm28 at gcc dot gnu.org]

http://sourceware.org/bugzilla/show_bug.cgi?id=13872

             Bug #: 13872
           Summary: powl (10, -LDBL_MAX) raises spurious overflow
                    exception
           Product: glibc
           Version: 2.15
            Status: NEW
          Severity: normal
          Priority: P2
         Component: math
        AssignedTo: unassigned@sourceware.org
        ReportedBy: jsm28@gcc.gnu.org
    Classification: Unclassified


powl (10, -LDBL_MAX) raises a spurious overflow exception (this is an underflow
case, not overflow) on x86 and x86_64.  Testcase:

#include <errno.h>
#include <fenv.h>
#include <math.h>
#include <stdio.h>
#include <float.h>

volatile long double d1 = 10, d2 = -LDBL_MAX;

int
main (void)
{
  feclearexcept (FE_ALL_EXCEPT);
  errno = 0;
  volatile long double r = powl (d1, d2);
  if (fetestexcept (FE_DIVBYZERO))
    printf ("DIVBYZERO ");
  if (fetestexcept (FE_INEXACT))
    printf ("INEXACT ");
  if (fetestexcept (FE_INVALID))
    printf ("INVALID ");
  if (fetestexcept (FE_OVERFLOW))
    printf ("OVERFLOW ");
  if (fetestexcept (FE_UNDERFLOW))
    printf ("UNDERFLOW ");
  printf ("%.18Lg %m\n", r);
  return 0;
}

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[Bug math/13872] powl (10, -LDBL_MAX) raises spurious overflow exception

[jsm28 at gcc dot gnu.org]

http://sourceware.org/bugzilla/show_bug.cgi?id=13872

Joseph Myers <jsm28 at gcc dot gnu.org> changed:

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

--- Comment #1 from Joseph Myers <jsm28 at gcc dot gnu.org> 2012-04-09 22:36:13 UTC ---
Fixed by:

commit 8f9a2faee0619ed5fad7b9c54b64f866b0264bde
Author: Joseph Myers <joseph@codesourcery.com>
Date:   Mon Apr 9 22:32:45 2012 +0000

    Fix spurious overflow exceptions from x86/x86_64 powl (bug 13872).

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[Bug math/13872] powl (10, -LDBL_MAX) raises spurious overflow exception

[fweimer at redhat dot com]

https://sourceware.org/bugzilla/show_bug.cgi?id=13872

Florian Weimer <fweimer at redhat dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
              Flags|                            |security-

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