result of erfc is never more precise than double

5 results were exact to double the precision

20 largest ulp errors (stored in a double)
   8985476322025521.00000 ulp for erfc(10.258082060821584) = 0)
   8985476316213586.00000 ulp for erfc(10.258082060852963) = 0)
   8985476316069151.00000 ulp for erfc(10.258082060853743) = 0)
   8985476316058952.00000 ulp for erfc(10.258082060853798) = 0)
   8985476316058623.00000 ulp for erfc(10.2580820608538) = 0)
   8985476315709873.00000 ulp for erfc(10.258082060855683) = 0)
   8985476308231840.00000 ulp for erfc(10.258082060896058) = 0)
   8880464479008878.00000 ulp for erfc(12.503458663385105) = 0)
   8880464469456238.00000 ulp for erfc(12.503458663427985) = 0)
   8880464469314565.00000 ulp for erfc(12.503458663428621) = 0)
   8880464469308629.00000 ulp for erfc(12.503458663428647) = 0)
   8880464469295174.00000 ulp for erfc(12.503458663428708) = 0)
   8880464469217610.00000 ulp for erfc(12.503458663429056) = 0)
   8880464468701573.00000 ulp for erfc(12.503458663431372) = 0)
   8866288373838710.00000 ulp for erfc(13.176291413317939) = 0)
   8866288323944790.00000 ulp for erfc(13.176291413530871) = 0)
   8866288323900254.00000 ulp for erfc(13.176291413531061) = 0)
   8866288323887766.00000 ulp for erfc(13.176291413531114) = 0)
   8866288321790366.00000 ulp for erfc(13.176291413540065) = 0)
   8565740390476948.00000 ulp for erfc(13.590757731732468) = 0)

<tr><td align=left><a href=erfc.res>erfc</a></td><td align=right>1318</td><td align=right>8985476322025521.00000</td><td>10.258082060821584</td><td>0</td></tr>