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1 // Copyright (C) 2017 Free Software Foundation, Inc.
3 // This file is part of the GNU ISO C++ Library. This library is free
4 // software; you can redistribute it and/or modify it under the
5 // terms of the GNU General Public License as published by the
6 // Free Software Foundation; either version 3, or (at your option)
9 // This library is distributed in the hope that it will be useful,
10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 // GNU General Public License for more details.
14 // You should have received a copy of the GNU General Public License along
15 // with this library; see the file COPYING3. If not see
16 // <http://www.gnu.org/licenses/>.
18 // PR libstdc++/68397 - std::tr1::expint fails in __expint_En_cont_frac
19 // for some long double arguments due to low __max_iter value
22 #include <testsuite_hooks.h>
27 // Answers from Wolfram Alpha.
28 long double ans_ok
= -0.10001943365331651406888645149537315243646135979573L;
29 long double ans_bomb
= -0.10777727809650077516264612749163100483995270163783L;
31 long double Ei_ok
= std::tr1::expint(-1.500001L);
32 long double diff_ok
= std::abs(Ei_ok
- ans_ok
);
33 VERIFY(diff_ok
< 1.0e-15L);
35 long double Ei_bomb
= std::tr1::expint(-1.450001L);
36 long double diff_bomb
= std::abs(Ei_bomb
- ans_bomb
);
37 VERIFY(diff_bomb
< 1.0e-15L);