libstdc++-v3/testsuite/27_io/basic_ostream/inserters_arithmetic/char/6.cc

   1 // 1999-11-15 Kevin Ediger  <kediger@licor.com>
   2 // test the floating point inserters (facet num_put)
   3
   4 // Copyright (C) 1999, 2002, 2003, 2005 Free Software Foundation, Inc.
   5 //
   6 // This file is part of the GNU ISO C++ Library.  This library is free
   7 // software; you can redistribute it and/or modify it under the
   8 // terms of the GNU General Public License as published by the
   9 // Free Software Foundation; either version 2, or (at your option)
  10 // any later version.
  11
  12 // This library is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16
  17 // You should have received a copy of the GNU General Public License along
  18 // with this library; see the file COPYING.  If not, write to the Free
  19 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  20 // USA.
  21
  22 #include <cmath> // for abs
  23 #include <cfloat> // for DBL_EPSILON
  24 #include <sstream>
  25 #include <limits>
  26 #include <testsuite_hooks.h>
  27
  28 // libstdc++/9151
  29 void
  30 test06()
  31 {
  32   using namespace std;
  33   bool test __attribute__((unused)) = true;
  34
  35   int prec = numeric_limits<double>::digits10 + 2;
  36   double oval = numeric_limits<double>::min();
  37
  38   stringstream ostr;
  39   ostr.precision(prec);
  40   ostr << oval;
  41   string sval = ostr.str();
  42   istringstream istr (sval);
  43   double ival;
  44   istr >> ival;
  45   VERIFY( abs(oval-ival)/oval < DBL_EPSILON );
  46 }
  47
  48 int
  49 main()
  50 {
  51   test06();
  52   return 0;
  53 }