diff options
author | Jonathan Wakely <jwakely@redhat.com> | 2018-10-18 16:38:50 +0100 |
---|---|---|
committer | Jonathan Wakely <redi@gcc.gnu.org> | 2018-10-18 16:38:50 +0100 |
commit | fab2c75b73c11d5c6d652a20bfa34e1733f1407f (patch) | |
tree | ceb55f655207d0eb8205ce2feba2e21d59e1cd64 /libstdc++-v3/testsuite | |
parent | b71679934e64bdad94409ace50ee79471cad6f20 (diff) | |
download | gcc-fab2c75b73c11d5c6d652a20bfa34e1733f1407f.tar.gz |
PR libstdc++/87641 correctly initialize accumulator in valarray::sum()
Use the value of the first element as the initial value of the
__valarray_sum accumulator. Value-initialization might not create the
additive identity for the value type.
Make a similar change to __valarray_product even though it's only ever
used internally with a value_type of size_t.
PR libstdc++/87641
* include/bits/valarray_array.h (__valarray_sum): Use first element
to initialize accumulator instead of value-initializing it.
(__valarray_product<_Tp>): Move to ...
* src/c++98/valarray.cc (__valarray_product<_Tp>): Here. Use first
element to initialize accumulator.
(__valarray_product(const valarray<size_t>&)): Remove const_cast made
unnecessary by LWG 389.
* testsuite/26_numerics/valarray/87641.cc: New test.
From-SVN: r265270
Diffstat (limited to 'libstdc++-v3/testsuite')
-rw-r--r-- | libstdc++-v3/testsuite/26_numerics/valarray/87641.cc | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/libstdc++-v3/testsuite/26_numerics/valarray/87641.cc b/libstdc++-v3/testsuite/26_numerics/valarray/87641.cc new file mode 100644 index 00000000000..eae5440e60b --- /dev/null +++ b/libstdc++-v3/testsuite/26_numerics/valarray/87641.cc @@ -0,0 +1,75 @@ +// Copyright (C) 2018 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 +// <http://www.gnu.org/licenses/>. + +#include <valarray> +#include <testsuite_hooks.h> + +void +test01() +{ + // PR libstdc++/87641 + std::valarray<int> v1(3); + v1[0] = 1; + v1[1] = 2; + v1[2] = 3; + std::valarray< std::valarray<int> > v2(v1, 3); + std::valarray<int> v3 = v2.sum(); + VERIFY( v3.size() == v1.size() ); + VERIFY( v3[0] == 3 ); + VERIFY( v3[1] == 6 ); + VERIFY( v3[2] == 9 ); +} + +struct X +{ + X() : val(1) { } + + X& operator+=(const X& x) { val += x.val; return *this; } + bool operator==(const X& x) { return val == x.val; } + + int val; +}; + +void +test02() +{ + std::valarray<X> v1(1); + VERIFY( v1.sum() == v1[0] ); + + std::valarray<X> v2(2); + VERIFY( v2.sum().val == 2 ); +} + +struct Y +{ + X& operator+=(const Y&) { throw 1; } +}; + +void +test03() +{ + std::valarray<Y> v1(1); + (void) v1.sum(); // no addition performed for a single element +} + +int +main() +{ + test01(); + test02(); + test03(); +} |