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<a name="Examining-floating-point-registers"></a>
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<p>
Next: <a href="Handling-floating-point-exceptions.html#Handling-floating-point-exceptions" accesskey="n" rel="next">Handling floating point exceptions</a>, Previous: <a href="Using-gdb.html#Using-gdb" accesskey="p" rel="previous">Using gdb</a>, Up: <a href="Debugging-Numerical-Programs.html#Debugging-Numerical-Programs" accesskey="u" rel="up">Debugging Numerical Programs</a> &nbsp; [<a href="Function-Index.html#Function-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Examining-floating-point-registers-1"></a>
<h3 class="section">A.2 Examining floating point registers</h3>
<a name="index-floating-point-registers"></a>

<p>The contents of floating point registers can be examined using the
command <code>info float</code> (on supported platforms).
</p>
<div class="smallexample">
<pre class="smallexample">(gdb) info float
     st0: 0xc4018b895aa17a945000  Valid Normal -7.838871e+308
     st1: 0x3ff9ea3f50e4d7275000  Valid Normal 0.0285946
     st2: 0x3fe790c64ce27dad4800  Valid Normal 6.7415931e-08
     st3: 0x3ffaa3ef0df6607d7800  Spec  Normal 0.0400229
     st4: 0x3c028000000000000000  Valid Normal 4.4501477e-308
     st5: 0x3ffef5412c22219d9000  Zero  Normal 0.9580257
     st6: 0x3fff8000000000000000  Valid Normal 1
     st7: 0xc4028b65a1f6d243c800  Valid Normal -1.566206e+309
   fctrl: 0x0272 53 bit; NEAR; mask DENOR UNDER LOS;
   fstat: 0xb9ba flags 0001; top 7; excep DENOR OVERF UNDER LOS
    ftag: 0x3fff
     fip: 0x08048b5c
     fcs: 0x051a0023
  fopoff: 0x08086820
  fopsel: 0x002b
</pre></div>

<p>Individual registers can be examined using the variables <var>$reg</var>,
where <var>reg</var> is the register name.
</p>
<div class="smallexample">
<pre class="smallexample">(gdb) p $st1 
$1 = 0.02859464454261210347719
</pre></div>




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