From 3808dfec58ef17c44b36dda7c2bb590580f6d8fc Mon Sep 17 00:00:00 2001
From: Benjamin Kosnik <bkoz@redhat.com>
Date: Fri, 16 Oct 2009 07:47:33 +0000
Subject: [PATCH] re PR libstdc++/40654 ([C++0x] atomic.cc: 'd' is used
uninitialized warning)
2009-10-15 Benjamin Kosnik <bkoz@redhat.com>
PR libstdc++/40654
PR libstdc++/40826
* src/atomic.cc (atomic_flag_test_and_set_explicit): Add
static_cast from base to derived.
(atomic_flag_clear_explicit): Same.
* include/bits/atomic_2.h (__atomic2::atomic_flag): Public derivation.
Remove value type constructor.
* include/bits/atomic_0.h (__atomic0::atomic_flag): Same.
* include/std/future (_Future_state): Use ATOMIC_FLAG_INIT to
initialized the atomic_flag member.
From-SVN: r152895
---
libstdc++-v3/ChangeLog | 13 +++++++
libstdc++-v3/include/bits/atomic_0.h | 5 +--
libstdc++-v3/include/bits/atomic_2.h | 5 +--
libstdc++-v3/include/std/future | 2 +-
libstdc++-v3/src/atomic.cc | 8 ++---
.../29_atomics/atomic_flag/clear/1.c | 34 +++++++++++++++++++
.../29_atomics/atomic_flag/clear/1.cc | 33 ++++++++++++++++++
7 files changed, 91 insertions(+), 9 deletions(-)
create mode 100644 libstdc++-v3/testsuite/29_atomics/atomic_flag/clear/1.c
create mode 100644 libstdc++-v3/testsuite/29_atomics/atomic_flag/clear/1.cc
diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index b19ae1bdfe77..4f8367eaff0e 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,16 @@
+2009-10-15 Benjamin Kosnik <bkoz@redhat.com>
+
+ PR libstdc++/40654
+ PR libstdc++/40826
+ * src/atomic.cc (atomic_flag_test_and_set_explicit): Add
+ static_cast from base to derived.
+ (atomic_flag_clear_explicit): Same.
+ * include/bits/atomic_2.h (__atomic2::atomic_flag): Public derivation.
+ Remove value type constructor.
+ * include/bits/atomic_0.h (__atomic0::atomic_flag): Same.
+ * include/std/future (_Future_state): Use ATOMIC_FLAG_INIT to
+ initialized the atomic_flag member.
+
2009-10-14 Benjamin Kosnik <bkoz@redhat.com>
* doc/xml/authors.xml: Update.
diff --git a/libstdc++-v3/include/bits/atomic_0.h b/libstdc++-v3/include/bits/atomic_0.h
index a493ea66af97..0caffaf1e9fb 100644
--- a/libstdc++-v3/include/bits/atomic_0.h
+++ b/libstdc++-v3/include/bits/atomic_0.h
@@ -82,14 +82,15 @@ namespace __atomic0
__r; })
/// atomic_flag
- struct atomic_flag : private __atomic_flag_base
+ struct atomic_flag : public __atomic_flag_base
{
atomic_flag() = default;
~atomic_flag() = default;
atomic_flag(const atomic_flag&) = delete;
atomic_flag& operator=(const atomic_flag&) = delete;
- atomic_flag(bool __i) { _M_i = __i; } // XXX deleted copy ctor != agg
+ // Conversion to ATOMIC_FLAG_INIT.
+ atomic_flag(bool __i): __atomic_flag_base({ __i }) { }
bool
test_and_set(memory_order __m = memory_order_seq_cst) volatile;
diff --git a/libstdc++-v3/include/bits/atomic_2.h b/libstdc++-v3/include/bits/atomic_2.h
index 8e8e7ff16f8c..d39adb920a25 100644
--- a/libstdc++-v3/include/bits/atomic_2.h
+++ b/libstdc++-v3/include/bits/atomic_2.h
@@ -44,14 +44,15 @@
namespace __atomic2
{
/// atomic_flag
- struct atomic_flag : private __atomic_flag_base
+ struct atomic_flag : public __atomic_flag_base
{
atomic_flag() = default;
~atomic_flag() = default;
atomic_flag(const atomic_flag&) = delete;
atomic_flag& operator=(const atomic_flag&) = delete;
- atomic_flag(bool __i) { _M_i = __i; } // XXX deleted copy ctor != agg
+ // Conversion to ATOMIC_FLAG_INIT.
+ atomic_flag(bool __i): __atomic_flag_base({ __i }) { }
bool
test_and_set(memory_order __m = memory_order_seq_cst) volatile
diff --git a/libstdc++-v3/include/std/future b/libstdc++-v3/include/std/future
index badb6e07e5a5..f922dcd74d5b 100644
--- a/libstdc++-v3/include/std/future
+++ b/libstdc++-v3/include/std/future
@@ -150,7 +150,7 @@ namespace std
typedef _Future_ptr<_Future_result_base>::type _Future_ptr_type;
public:
- _Future_state() : _M_result(), _M_retrieved(false) { }
+ _Future_state() : _M_result(), _M_retrieved(ATOMIC_FLAG_INIT) { }
_Future_state(const _Future_state&) = delete;
_Future_state& operator=(const _Future_state&) = delete;
diff --git a/libstdc++-v3/src/atomic.cc b/libstdc++-v3/src/atomic.cc
index 3a2ff3d52e92..775bb7601c17 100644
--- a/libstdc++-v3/src/atomic.cc
+++ b/libstdc++-v3/src/atomic.cc
@@ -80,16 +80,16 @@ namespace std
atomic_flag_test_and_set_explicit(volatile __atomic_flag_base* __a,
memory_order __m) throw ()
{
- volatile atomic_flag d(__a->_M_i);
- return d.test_and_set(__m);
+ volatile atomic_flag* d = static_cast<volatile atomic_flag*>(__a);
+ return d->test_and_set(__m);
}
void
atomic_flag_clear_explicit(volatile __atomic_flag_base* __a,
memory_order __m) throw ()
{
- volatile atomic_flag d(__a->_M_i);
- return d.clear(__m);
+ volatile atomic_flag* d = static_cast<volatile atomic_flag*>(__a);
+ return d->clear(__m);
}
void
diff --git a/libstdc++-v3/testsuite/29_atomics/atomic_flag/clear/1.c b/libstdc++-v3/testsuite/29_atomics/atomic_flag/clear/1.c
new file mode 100644
index 000000000000..3fd2f2c799d2
--- /dev/null
+++ b/libstdc++-v3/testsuite/29_atomics/atomic_flag/clear/1.c
@@ -0,0 +1,34 @@
+// { dg-options "-x c -shared-libgcc -lstdc++" }
+
+// Copyright (C) 2009 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 <cassert>
+#include <stdatomic.h>
+
+// libstdc++/40826
+// libstdc++/40654
+int main()
+{
+ atomic_flag f = ATOMIC_FLAG_INIT;
+
+ atomic_flag_clear(&f); // set to false
+ assert( false == atomic_flag_test_and_set(&f) ); // return previous false, set to true
+ assert( true == atomic_flag_test_and_set(&f) ); // return true
+
+ return 0;
+}
diff --git a/libstdc++-v3/testsuite/29_atomics/atomic_flag/clear/1.cc b/libstdc++-v3/testsuite/29_atomics/atomic_flag/clear/1.cc
new file mode 100644
index 000000000000..6cb09f34b7a1
--- /dev/null
+++ b/libstdc++-v3/testsuite/29_atomics/atomic_flag/clear/1.cc
@@ -0,0 +1,33 @@
+// { dg-options "-std=gnu++0x" }
+
+// Copyright (C) 2009 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 <cstdatomic>
+#include <testsuite_hooks.h>
+
+int main()
+{
+ bool test __attribute__((unused)) = true;
+ std::atomic_flag f = ATOMIC_FLAG_INIT;
+
+ f.clear(); // set to false
+ VERIFY( false == f.test_and_set() ); // return previous false, set to true
+ VERIFY( true == f.test_and_set() ); // return true
+
+ return 0;
+}
--
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