[Bug libstdc++/11099] New: wrong values for numeric_limits<double>

[franky.backeljauw@ua.ac.be]

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11099

           Summary: wrong values for numeric_limits<double>
           Product: gcc
           Version: 3.2.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: libstdc++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: franky.backeljauw@ua.ac.be
                CC: gcc-bugs@gcc.gnu.org
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu (redhat-linux-9, gcc version 3.2.2,
                    intel pent
GCC target triplet: i386-pc-linux-gnu

Hello,

could there be an error in the values of the numeric_limits<double>
specification?  It gives me (Intel, RH9) the following values

<snip>
TYPE = double
  is_specialized = 1
  radix = 2
  digits = 53
  digits10 = 15
  is_signed = 1
  is_integer = 0
  is_exact = 0
  min = 2.22507e-308
  max = 1.79769e+308
  epsilon = 2.22045e-16
  round_error = 1
  min_exponent = -1021
  max_exponent = 1024
  min_exponent10 = -307
  max_exponent10 = 308
  is_iec559 = 0
  is_bounded = 1
  is_modulo = 0
  traps = 0
  tinyness_before = 0
</snip>

I found some documentation on the "numeric_limits" class which states that

<snip>
  max_exponent = Maximum positive integer such that the radix raised to
                 that power is in range.
  min_exponent = Minimum negative integer such that the radix raised to
                 that power is in range.
</snip>

This would mean that both values are wrong according to both the IEEE 854
standard as well as the definitions given above.  Using the definition,
min_exponent should for instance be -1022 - 52 or -1074 for the double type,
whilst using the standard it should be just -1022.  max_exponent should in both
cases be 1023.

Also, is_iec559 is false, which would mean that the type is not IEEE 854 compliant?



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