[Bug math/369] New: pow problems on x86

[vargaz at gmail dot com]

Consider the following test program:
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
#include <stdio.h>
#include <math.h>

void main() {
        double d;

        d = pow (-2, 1E300);
        printf ("D: %f.\n", d);

        d = pow (-2, -1E300);
        printf ("D: %f.\n", d);
}
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

Under x86 linux, this prints out:

D: nan.
D: nan

I think the answer should be +inf and 0, respectively. Both
solaris,
windows, and the IBM Accurate Portable Mathematical library
returns
these values, so I think this might be a bug in the assembly
language
pow routine in glibc.

-- 
           Summary: pow problems on x86
           Product: glibc
           Version: 2.3.2
            Status: NEW
          Severity: normal
          Priority: P2
         Component: math
        AssignedTo: aj at suse dot de
        ReportedBy: vargaz at gmail dot com
                CC: glibc-bugs at sources dot redhat dot com
  GCC host triplet: i686-pc-linux-gnu


http://sources.redhat.com/bugzilla/show_bug.cgi?id=369

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