[Bug math/13940] New: acos returns wrong value

[Bug math/13940] New: acos returns wrong value

[michael.blumenkrantz at gmail dot com]

http://sourceware.org/bugzilla/show_bug.cgi?id=13940

             Bug #: 13940
           Summary: acos returns wrong value
           Product: glibc
           Version: 2.14
            Status: NEW
          Severity: normal
          Priority: P2
         Component: math
        AssignedTo: unassigned@sourceware.org
        ReportedBy: michael.blumenkrantz@gmail.com
    Classification: Unclassified


acos(-1) should return pi, but on my system it returns 0.

This is the same bug as in
http://sourceware.org/ml/libc-help/2008-09/msg00031.html

my version of glibc is 2.14.1

-- 
Configure bugmail: http://sourceware.org/bugzilla/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are on the CC list for the bug.

[Bug math/13940] acos returns wrong value

[aj at suse dot de]

http://sourceware.org/bugzilla/show_bug.cgi?id=13940

Andreas Jaeger <aj at suse dot de> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
                 CC|                            |aj at suse dot de
         Resolution|                            |WORKSFORME

--- Comment #1 from Andreas Jaeger <aj at suse dot de> 2012-04-03 07:37:58 UTC ---
I just wrote a short test program to confirm that the test we have in the math
testsuite for acos(-1) is working:

#include <math.h>
#include <stdio.h>

int
main (void)
{
  float f;
  double d;
  long double ld;

  f = acosf (-1.0f);
  d = acos (-1.0);
  ld = acosl (-1.0);

  printf ("float %f\n", f);
  printf ("double %f\n", d);
  printf ("long double %Lf\n", ld);

  return 0;
}

It returns on my glibc 2.15 system:

aj@byrd:/tmp> gcc -Wall -lm t.c
aj@byrd:/tmp> ./a.out 
float 3.141593
double 3.141593
long double 3.141593

So, everything is fine.

If it does not work for you, please attach a short selfcontained test case and
example output.

Closing as WORKSFORME - feel free to reopen if you have additional data.

The issue mentioned in libc-help is something different and as Carlos said, it
needs a separate bug report.

-- 
Configure bugmail: http://sourceware.org/bugzilla/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are on the CC list for the bug.

[Bug math/13940] acos returns wrong value

[fweimer at redhat dot com]

https://sourceware.org/bugzilla/show_bug.cgi?id=13940

Florian Weimer <fweimer at redhat dot com> changed:

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

-- 
You are receiving this mail because:
You are on the CC list for the bug.