[PATCH] Fix exception-specifications for std::_Not_fn
Jonathan Wakely
jwakely@redhat.com
Thu Oct 13 10:19:00 GMT 2016
The exception specifications for _Not_fn::operator() should consider
whether operator! on the result can throw.
* include/std/functional (_Not_fn): Make exception specifications
depend on whether negating the result can throw.
* testsuite/20_util/not_fn/1.cc: Move to ...
* testsuite/20_util/function_objects/not_fn/1.cc: ... here. Add tests
for types that can throw when negated and that cannot be negated.
Tested powerpc64le-linux, committed to trunk.
-------------- next part --------------
commit 333bf1f483cb3ba215fe959867310c7d2dd99e58
Author: Jonathan Wakely <jwakely@redhat.com>
Date: Thu Oct 13 10:34:43 2016 +0100
Fix exception-specifications for std::_Not_fn
* include/std/functional (_Not_fn): Make exception specifications
depend on whether negating the result can throw.
* testsuite/20_util/not_fn/1.cc: Move to ...
* testsuite/20_util/function_objects/not_fn/1.cc: ... here. Add tests
for types that can throw when negated and that cannot be negated.
diff --git a/libstdc++-v3/include/std/functional b/libstdc++-v3/include/std/functional
index 6a45314..58134b7 100644
--- a/libstdc++-v3/include/std/functional
+++ b/libstdc++-v3/include/std/functional
@@ -2140,6 +2140,16 @@ _GLIBCXX_MEM_FN_TRAITS(&&, false_type, true_type)
template<typename _Fn>
class _Not_fn
{
+ template<typename _Tp>
+ using __is_nothrow_negatable
+ = __bool_constant<noexcept(!std::declval<_Tp>())>;
+
+ template<typename _Fn2, typename... _Args>
+ using __noexcept_cond = __and_<
+ __is_nothrow_callable<_Fn2(_Args&&...)>,
+ __is_nothrow_negatable<result_of_t<_Fn2(_Args&&...)>>
+ >;
+
public:
template<typename _Fn2>
_Not_fn(_Fn2&& __fn, int)
@@ -2152,21 +2162,21 @@ _GLIBCXX_MEM_FN_TRAITS(&&, false_type, true_type)
template<typename... _Args>
auto
operator()(_Args&&... __args) &
- noexcept(__is_nothrow_callable<_Fn&(_Args&&...)>::value)
+ noexcept(__noexcept_cond<_Fn&, _Args&&...>::value)
-> decltype(!std::declval<result_of_t<_Fn&(_Args&&...)>>())
{ return !std::__invoke(_M_fn, std::forward<_Args>(__args)...); }
template<typename... _Args>
auto
operator()(_Args&&... __args) const &
- noexcept(__is_nothrow_callable<const _Fn&(_Args&&...)>::value)
+ noexcept(__noexcept_cond<const _Fn&, _Args&&...>::value)
-> decltype(!std::declval<result_of_t<const _Fn&(_Args&&...)>>())
{ return !std::__invoke(_M_fn, std::forward<_Args>(__args)...); }
template<typename... _Args>
auto
operator()(_Args&&... __args) &&
- noexcept(__is_nothrow_callable<_Fn&&(_Args&&...)>::value)
+ noexcept(__noexcept_cond<_Fn&&, _Args&&...>::value)
-> decltype(!std::declval<result_of_t<_Fn&&(_Args&&...)>>())
{
return !std::__invoke(std::move(_M_fn),
@@ -2176,7 +2186,7 @@ _GLIBCXX_MEM_FN_TRAITS(&&, false_type, true_type)
template<typename... _Args>
auto
operator()(_Args&&... __args) const &&
- noexcept(__is_nothrow_callable<const _Fn&&(_Args&&...)>::value)
+ noexcept(__noexcept_cond<const _Fn&&, _Args&&...>::value)
-> decltype(!std::declval<result_of_t<const _Fn&&(_Args&&...)>>())
{
return !std::__invoke(std::move(_M_fn),
diff --git a/libstdc++-v3/testsuite/20_util/function_objects/not_fn/1.cc b/libstdc++-v3/testsuite/20_util/function_objects/not_fn/1.cc
new file mode 100644
index 0000000..246b962
--- /dev/null
+++ b/libstdc++-v3/testsuite/20_util/function_objects/not_fn/1.cc
@@ -0,0 +1,133 @@
+// Copyright (C) 2014-2016 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/>.
+
+// { dg-options "-std=gnu++17" }
+
+#include <functional>
+#include <testsuite_hooks.h>
+
+using std::not_fn;
+
+int func(int, char) { return 0; }
+
+struct F
+{
+ bool operator()() { return false; }
+ bool operator()() const { return true; }
+ bool operator()(int) { return false; }
+};
+
+void
+test01()
+{
+ auto f1 = not_fn(func);
+ VERIFY( f1(1, '2') == true );
+
+ auto f2 = not_fn( [] { return true; } );
+ VERIFY( f2() == false );
+
+ auto f3 = not_fn( F{} );
+ VERIFY( f3() == true );
+ VERIFY( f3(1) == true );
+ const auto f4 = f3;
+ VERIFY( f4() == false );
+}
+
+template<typename F, typename Arg>
+auto foo(F f, Arg arg) -> decltype(not_fn(f)(arg)) { return not_fn(f)(arg); }
+
+template<typename F, typename Arg>
+auto foo(F f, Arg arg) -> decltype(not_fn(f)()) { return not_fn(f)(); }
+
+struct negator
+{
+ bool operator()(int) const { return false; }
+ void operator()() const {}
+};
+
+void
+test02()
+{
+ foo(negator{}, 1); // PR libstdc++/66998
+}
+
+void
+test03()
+{
+ struct X { bool b; };
+ X x{ false };
+ VERIFY( not_fn(&X::b)(x) );
+}
+
+void
+test04()
+{
+ struct abstract { virtual void f() = 0; };
+ struct derived : abstract { void f() { } };
+ struct F { bool operator()(abstract&) { return false; } };
+ F f;
+ derived d;
+ VERIFY( not_fn(f)(d) );
+}
+
+void
+test05()
+{
+ auto nf = std::not_fn([] { return false; });
+ auto copy(nf); // PR libstdc++/70564
+}
+
+void
+test06()
+{
+ struct Boolean {
+ Boolean operator!() noexcept(false) { return *this; }
+ };
+ struct F {
+ Boolean operator()() { return {}; }
+ };
+ F f;
+ auto notf = std::not_fn(f);
+ using NotF = decltype(notf);
+ static_assert( std::is_callable<NotF()>::value, "cannot negate" );
+ static_assert( !noexcept(notf()), "conversion to bool affects noexcept" );
+}
+
+void
+test07()
+{
+ struct NonNegatable { };
+ struct F {
+ NonNegatable operator()() { return {}; }
+ };
+ F f;
+ auto notf = std::not_fn(f);
+ using NotF = decltype(notf);
+ static_assert( !std::is_callable<NotF()>::value, "cannot negate" );
+}
+
+int
+main()
+{
+ test01();
+ test02();
+ test03();
+ test04();
+ test05();
+ test06();
+ test07();
+}
diff --git a/libstdc++-v3/testsuite/20_util/not_fn/1.cc b/libstdc++-v3/testsuite/20_util/not_fn/1.cc
deleted file mode 100644
index 233a6d3..0000000
--- a/libstdc++-v3/testsuite/20_util/not_fn/1.cc
+++ /dev/null
@@ -1,102 +0,0 @@
-// Copyright (C) 2014-2016 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/>.
-
-// { dg-options "-std=gnu++17" }
-
-#include <functional>
-#include <testsuite_hooks.h>
-
-using std::not_fn;
-
-int func(int, char) { return 0; }
-
-struct F
-{
- bool operator()() { return false; }
- bool operator()() const { return true; }
- bool operator()(int) { return false; }
-};
-
-void
-test01()
-{
- auto f1 = not_fn(func);
- VERIFY( f1(1, '2') == true );
-
- auto f2 = not_fn( [] { return true; } );
- VERIFY( f2() == false );
-
- auto f3 = not_fn( F{} );
- VERIFY( f3() == true );
- VERIFY( f3(1) == true );
- const auto f4 = f3;
- VERIFY( f4() == false );
-}
-
-template<typename F, typename Arg>
-auto foo(F f, Arg arg) -> decltype(not_fn(f)(arg)) { return not_fn(f)(arg); }
-
-template<typename F, typename Arg>
-auto foo(F f, Arg arg) -> decltype(not_fn(f)()) { return not_fn(f)(); }
-
-struct negator
-{
- bool operator()(int) const { return false; }
- void operator()() const {}
-};
-
-void
-test02()
-{
- foo(negator{}, 1); // PR libstdc++/66998
-}
-
-void
-test03()
-{
- struct X { bool b; };
- X x{ false };
- VERIFY( not_fn(&X::b)(x) );
-}
-
-void
-test04()
-{
- struct abstract { virtual void f() = 0; };
- struct derived : abstract { void f() { } };
- struct F { bool operator()(abstract&) { return false; } };
- F f;
- derived d;
- VERIFY( not_fn(f)(d) );
-}
-
-void
-test05()
-{
- auto nf = std::not_fn([] { return false; });
- auto copy(nf); // PR libstdc++/70564
-}
-
-int
-main()
-{
- test01();
- test02();
- test03();
- test04();
- test05();
-}
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