From 116e3cfc7b8ab8afc4bdbc03db6b194413218af7 Mon Sep 17 00:00:00 2001 From: Jonathan Wakely Date: Wed, 27 May 2020 13:13:19 +0100 Subject: [PATCH] libstdc++: Add new testcase for comparison category types Comparing a comparison category type to anything except a literal 0 is undefined. This verifies that at least some misuses are diagnosed at compile time. * testsuite/18_support/comparisons/categories/zero_neg.cc: New test. --- .../comparisons/categories/zero_neg.cc | 46 +++++++++++++++++++ 1 file changed, 46 insertions(+) create mode 100644 libstdc++-v3/testsuite/18_support/comparisons/categories/zero_neg.cc diff --git a/libstdc++-v3/testsuite/18_support/comparisons/categories/zero_neg.cc b/libstdc++-v3/testsuite/18_support/comparisons/categories/zero_neg.cc new file mode 100644 index 00000000000..0a8af41acb9 --- /dev/null +++ b/libstdc++-v3/testsuite/18_support/comparisons/categories/zero_neg.cc @@ -0,0 +1,46 @@ +// Copyright (C) 2020 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 +// . + +// { dg-options "-std=gnu++2a" } +// { dg-do compile { target c++2a } } + +#include + +// C++20 [cmp.categories.pre] +// "an argument other than a literal 0 is undefined" + +void +test01() +{ + std::partial_ordering::equivalent == 0; // OK + std::weak_ordering::equivalent == 0; // OK + std::strong_ordering::equivalent == 0; // OK + + std::partial_ordering::equivalent == 1; // { dg-error "invalid conversion" } + std::weak_ordering::equivalent == 1; // { dg-error "invalid conversion" } + std::strong_ordering::equivalent == 1; // { dg-error "invalid conversion" } + + constexpr void* p = nullptr; + std::partial_ordering::equivalent == p; // { dg-error "invalid conversion" } + std::weak_ordering::equivalent == p; // { dg-error "invalid conversion" } + std::strong_ordering::equivalent == p; // { dg-error "invalid conversion" } + + // Ideally these would be ill-formed, but the current code accepts it. + std::partial_ordering::equivalent == nullptr; + std::weak_ordering::equivalent == nullptr; + std::strong_ordering::equivalent == nullptr; +} -- 2.30.2