From b5889d25e9bf944a89fdd7bcabf3b6c6f6bb6f7c Mon Sep 17 00:00:00 2001 From: Florian Weimer Date: Mon, 21 Aug 2017 13:03:29 +0200 Subject: assert: Support types without operator== (int) [BZ #21972] --- assert/tst-assert-c++.cc | 78 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 78 insertions(+) create mode 100644 assert/tst-assert-c++.cc (limited to 'assert/tst-assert-c++.cc') diff --git a/assert/tst-assert-c++.cc b/assert/tst-assert-c++.cc new file mode 100644 index 0000000000..12a5e690cb --- /dev/null +++ b/assert/tst-assert-c++.cc @@ -0,0 +1,78 @@ +/* Tests for interactions between C++ and assert. + Copyright (C) 2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include + +/* The C++ standard requires that if the assert argument is a constant + subexpression, then the assert itself is one, too. */ +constexpr int +check_constexpr () +{ + return (assert (true), 1); +} + +/* Objects of this class can be contextually converted to bool, but + cannot be compared to int. */ +struct no_int +{ + no_int () = default; + no_int (const no_int &) = delete; + + explicit operator bool () const + { + return true; + } + + bool operator! () const; /* No definition. */ + template bool operator== (T) const; /* No definition. */ + template bool operator!= (T) const; /* No definition. */ +}; + +/* This class tests that operator== is not used by assert. */ +struct bool_and_int +{ + bool_and_int () = default; + bool_and_int (const no_int &) = delete; + + explicit operator bool () const + { + return true; + } + + bool operator! () const; /* No definition. */ + template bool operator== (T) const; /* No definition. */ + template bool operator!= (T) const; /* No definition. */ +}; + +static int +do_test () +{ + { + no_int value; + assert (value); + } + + { + bool_and_int value; + assert (value); + } + + return 0; +} + +#include -- cgit v1.2.3