From 4ba07ed462c02f4de2205c3e2186a85e4d81fc2d Mon Sep 17 00:00:00 2001 From: Edward Smith-Rowland <3dw4rd@verizon.net> Date: Thu, 20 Apr 2017 15:41:59 +0000 Subject: [PATCH] PR libstdc++/68397 std::tr1::expint fails ... long double arguments. 2017-04-20 Edward Smith-Rowland <3dw4rd@verizon.net> PR libstdc++/68397 std::tr1::expint fails ... long double arguments. * include/tr1/exp_integral.tcc: Increase iteration limits. * testsuite/tr1/5_numerical_facilities/special_functions/15_expint/ pr68397.cc: New test. * testsuite/special_functions/14_expint/pr68397.cc: New test. From-SVN: r247027 --- libstdc++-v3/ChangeLog | 8 ++++ libstdc++-v3/include/tr1/exp_integral.tcc | 6 +-- .../special_functions/14_expint/pr68397.cc | 47 +++++++++++++++++++ .../special_functions/15_expint/pr68397.cc | 46 ++++++++++++++++++ 4 files changed, 104 insertions(+), 3 deletions(-) create mode 100644 libstdc++-v3/testsuite/special_functions/14_expint/pr68397.cc create mode 100644 libstdc++-v3/testsuite/tr1/5_numerical_facilities/special_functions/15_expint/pr68397.cc diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog index fa79d16c73f..7fb199875f2 100644 --- a/libstdc++-v3/ChangeLog +++ b/libstdc++-v3/ChangeLog @@ -1,3 +1,11 @@ +2017-04-20 Edward Smith-Rowland <3dw4rd@verizon.net> + + PR libstdc++/68397 std::tr1::expint fails ... long double arguments. + * include/tr1/exp_integral.tcc: Increase iteration limits. + * testsuite/tr1/5_numerical_facilities/special_functions/15_expint/ + pr68397.cc: New test. + * testsuite/special_functions/14_expint/pr68397.cc: New test. + 2017-04-20 Jonathan Wakely PR libstdc++/79862 diff --git a/libstdc++-v3/include/tr1/exp_integral.tcc b/libstdc++-v3/include/tr1/exp_integral.tcc index f33f234e6f6..8e6f55178e7 100644 --- a/libstdc++-v3/include/tr1/exp_integral.tcc +++ b/libstdc++-v3/include/tr1/exp_integral.tcc @@ -86,7 +86,7 @@ namespace tr1 _Tp __term = _Tp(1); _Tp __esum = _Tp(0); _Tp __osum = _Tp(0); - const unsigned int __max_iter = 100; + const unsigned int __max_iter = 1000; for (unsigned int __i = 1; __i < __max_iter; ++__i) { __term *= - __x / __i; @@ -156,7 +156,7 @@ namespace tr1 _Tp __expint_En_series(unsigned int __n, _Tp __x) { - const unsigned int __max_iter = 100; + const unsigned int __max_iter = 1000; const _Tp __eps = std::numeric_limits<_Tp>::epsilon(); const int __nm1 = __n - 1; _Tp __ans = (__nm1 != 0 @@ -202,7 +202,7 @@ namespace tr1 _Tp __expint_En_cont_frac(unsigned int __n, _Tp __x) { - const unsigned int __max_iter = 100; + const unsigned int __max_iter = 1000; const _Tp __eps = std::numeric_limits<_Tp>::epsilon(); const _Tp __fp_min = std::numeric_limits<_Tp>::min(); const int __nm1 = __n - 1; diff --git a/libstdc++-v3/testsuite/special_functions/14_expint/pr68397.cc b/libstdc++-v3/testsuite/special_functions/14_expint/pr68397.cc new file mode 100644 index 00000000000..8da16d1fc69 --- /dev/null +++ b/libstdc++-v3/testsuite/special_functions/14_expint/pr68397.cc @@ -0,0 +1,47 @@ +// { dg-do run { target c++11 } } +// { dg-options "-D__STDCPP_WANT_MATH_SPEC_FUNCS__" } +// Copyright (C) 2017 Free Software Foundation, Inc. +// +// This file is part of the GNU ISO C++ Library. This library is free +// software; you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the +// Free Software Foundation; either version 3, or (at your option) +// any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License along +// with this library; see the file COPYING3. If not see +// . + +// PR libstdc++/68397 - std::tr1::expint fails in __expint_En_cont_frac +// for some long double arguments due to low __max_iter value + +#include +#include + +int +test01() +{ + // Answers from Wolfram Alpha. + long double ans_ok = -0.10001943365331651406888645149537315243646135979573L; + long double ans_bomb = -0.10777727809650077516264612749163100483995270163783L; + + auto Ei_ok = std::expint(-1.500001L); + auto diff_ok = Ei_ok - ans_ok; + VERIFY(std::abs(diff_ok) < 1.0e-15); + + auto Ei_bomb = std::expint(-1.450001L); + auto diff_bomb = Ei_bomb - ans_bomb; + VERIFY(std::abs(diff_bomb) < 1.0e-15); +} + +int +main() +{ + test01(); + return 0; +} diff --git a/libstdc++-v3/testsuite/tr1/5_numerical_facilities/special_functions/15_expint/pr68397.cc b/libstdc++-v3/testsuite/tr1/5_numerical_facilities/special_functions/15_expint/pr68397.cc new file mode 100644 index 00000000000..60d0b68bad6 --- /dev/null +++ b/libstdc++-v3/testsuite/tr1/5_numerical_facilities/special_functions/15_expint/pr68397.cc @@ -0,0 +1,46 @@ +// Copyright (C) 2017 Free Software Foundation, Inc. +// +// This file is part of the GNU ISO C++ Library. This library is free +// software; you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the +// Free Software Foundation; either version 3, or (at your option) +// any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License along +// with this library; see the file COPYING3. If not see +// . + +// PR libstdc++/68397 - std::tr1::expint fails in __expint_En_cont_frac +// for some long double arguments due to low __max_iter value + +#include +#include + +void +test01() +{ + // Answers from Wolfram Alpha. + long double ans_ok = -0.10001943365331651406888645149537315243646135979573L; + long double ans_bomb = -0.10777727809650077516264612749163100483995270163783L; + + long double Ei_ok = std::tr1::expint(-1.500001L); + long double diff_ok = std::abs(Ei_ok - ans_ok); + VERIFY(diff_ok < 1.0e-15L); + + long double Ei_bomb = std::tr1::expint(-1.450001L); + long double diff_bomb = std::abs(Ei_bomb - ans_bomb); + VERIFY(diff_bomb < 1.0e-15L); +} + +int +main() +{ + test01(); + return 0; +} + -- 2.30.2