exception: Include nested_exception.h in C++0x mode.

2009-05-12  Jonathan Wakely  <jwakely.gcc@gmail.com>

	* libsupc++/exception: Include nested_exception.h in C++0x mode.
	* libsupc++/nested_exception.h: New.
	* libsupc++/Makefile.am: Add new header.
	* libsupc++/Makefile.in: Regenerate.
	* testsuite/18_support/nested_exception/rethrow_nested.cc: New.
	* testsuite/18_support/nested_exception/throw_with_nested.cc: New.
	* testsuite/18_support/nested_exception/cons.cc: New.
	* testsuite/18_support/nested_exception/nested_ptr.cc: New.
	* testsuite/18_support/nested_exception/rethrow_if_nested.cc: New.
	* doc/xml/manual/status_cxx200x.xml: Adjust.

From-SVN: r147446

4 files changed, 180 insertions, 2 deletions

diff --git a/libstdc++-v3/libsupc++/Makefile.am b/libstdc++-v3/libsupc++/Makefile.am
index 5c86a1e..b84b5e4 100644
--- a/libstdc++-v3/libsupc++/Makefile.am
+++ b/libstdc++-v3/libsupc++/Makefile.am
@@ -33,7 +33,7 @@ noinst_LTLIBRARIES = libsupc++convenience.la
 
 headers = \
 	exception new typeinfo cxxabi.h cxxabi-forced.h exception_defines.h \
-	initializer_list exception_ptr.h
+	initializer_list exception_ptr.h nested_exception.h
 
 if GLIBCXX_HOSTED
   c_sources = \
diff --git a/libstdc++-v3/libsupc++/Makefile.in b/libstdc++-v3/libsupc++/Makefile.in
index 26fbd54..50ede6a 100644
--- a/libstdc++-v3/libsupc++/Makefile.in
+++ b/libstdc++-v3/libsupc++/Makefile.in
@@ -367,7 +367,7 @@ toolexeclib_LTLIBRARIES = libsupc++.la
 noinst_LTLIBRARIES = libsupc++convenience.la
 headers = \
 	exception new typeinfo cxxabi.h cxxabi-forced.h exception_defines.h \
-	initializer_list exception_ptr.h
+	initializer_list exception_ptr.h nested_exception.h
 
 @GLIBCXX_HOSTED_TRUE@c_sources = \
 @GLIBCXX_HOSTED_TRUE@	cp-demangle.c 
diff --git a/libstdc++-v3/libsupc++/exception b/libstdc++-v3/libsupc++/exception
index c8b334f..be7dec6 100644
--- a/libstdc++-v3/libsupc++/exception
+++ b/libstdc++-v3/libsupc++/exception
@@ -146,6 +146,7 @@ _GLIBCXX_END_NAMESPACE
 #if (defined(__GXX_EXPERIMENTAL_CXX0X__) \
      && defined(_GLIBCXX_ATOMIC_BUILTINS_4))
 #include <exception_ptr.h>
+#include <nested_exception.h>
 #endif
 
 #endif
diff --git a/libstdc++-v3/libsupc++/nested_exception.h b/libstdc++-v3/libsupc++/nested_exception.h
new file mode 100644
index 0000000..752c595
--- /dev/null
+++ b/libstdc++-v3/libsupc++/nested_exception.h
@@ -0,0 +1,177 @@
+// Nested Exception support header (nested_exception class) for -*- C++ -*-
+
+// 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.
+
+// Under Section 7 of GPL version 3, you are granted additional
+// permissions described in the GCC Runtime Library Exception, version
+// 3.1, as published by the Free Software Foundation.
+
+// You should have received a copy of the GNU General Public License and
+// a copy of the GCC Runtime Library Exception along with this program;
+// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+// <http://www.gnu.org/licenses/>.
+
+/** @file nested_exception.h
+ *  This is an internal header file, included by other headers and the
+ *  implementation. You should not attempt to use it directly.
+ */
+
+#ifndef _GLIBCXX_NESTED_EXCEPTION_H
+#define _GLIBCXX_NESTED_EXCEPTION_H 1
+
+#pragma GCC visibility push(default)
+
+#ifndef __GXX_EXPERIMENTAL_CXX0X__
+# include <c++0x_warning.h>
+#else
+
+#include <bits/c++config.h>
+
+#if !defined(_GLIBCXX_ATOMIC_BUILTINS_4)
+#  error This platform does not support exception propagation.
+#endif
+
+extern "C++" {
+
+namespace std
+{
+  /**
+   * @addtogroup exceptions
+   * @{
+   */
+
+  /// nested_exception
+  class nested_exception
+  {
+  public:
+    nested_exception() throw() : _M_ptr(current_exception()) { }
+
+    nested_exception(const nested_exception&) throw() = default;
+
+    nested_exception& operator=(const nested_exception&) throw() = default;
+
+    virtual ~nested_exception() = default;
+
+    void
+    rethrow_nested() const __attribute__ ((__noreturn__))
+    { rethrow_exception(_M_ptr); }
+
+    exception_ptr
+    nested_ptr() const
+    { return _M_ptr; }
+
+  private:
+    exception_ptr _M_ptr;
+  };
+
+  template<typename _Except>
+    struct _Nested_exception : public _Except, public nested_exception
+    {
+      explicit
+      _Nested_exception(_Except&& __ex)
+      : _Except(static_cast<_Except&&>(__ex))
+      { }
+    };
+
+  template<typename _Ex>
+    struct __get_nested_helper
+    {
+      static const nested_exception*
+      _S_get(const _Ex& __ex)
+      {
+        return dynamic_cast<const nested_exception*>(&__ex);
+      }
+    };
+
+  template<typename _Ex>
+    struct __get_nested_helper<_Ex*>
+    {
+      static const nested_exception*
+      _S_get(const _Ex* __ex)
+      {
+        return dynamic_cast<const nested_exception*>(__ex);
+      }
+    };
+
+  template<typename _Ex>
+    inline const nested_exception*
+    __get_nested_exception(const _Ex& __ex)
+    {
+      return __get_nested_helper<_Ex>::_S_get(__ex);
+    }
+
+  template<typename _Ex>
+    void
+    __throw_with_nested(_Ex&&, const nested_exception* = 0)
+    __attribute__ ((__noreturn__));
+
+  template<typename _Ex>
+    void
+    __throw_with_nested(_Ex&&, ...) __attribute__ ((__noreturn__));
+
+  // This function should never be called, but is needed to avoid a warning
+  // about ambiguous base classes when instantiating throw_with_nested<_Ex>()
+  // with a type that has an accessible nested_exception base.
+  template<typename _Ex>
+    inline void
+    __throw_with_nested(_Ex&& __ex, const nested_exception* = 0)
+    {
+      throw __ex;
+    }
+
+  template<typename _Ex>
+    inline void
+    __throw_with_nested(_Ex&& __ex, ...)
+    {
+      throw _Nested_exception<_Ex>(static_cast<_Ex&&>(__ex));
+    }
+  
+  template<typename _Ex>
+    void
+    throw_with_nested(_Ex __ex) __attribute__ ((__noreturn__));
+
+  template<typename _Ex>
+    inline void
+    throw_with_nested(_Ex __ex)
+    {
+      if (__get_nested_exception(__ex))
+        throw __ex;
+      __throw_with_nested(static_cast<_Ex&&>(__ex), &__ex);
+    }
+
+  template<typename _Ex>
+    inline void
+    rethrow_if_nested(const _Ex& __ex)
+    {
+      if (const nested_exception* __nested = __get_nested_exception(__ex))
+        __nested->rethrow_nested();
+    }
+
+  // see n2619
+  inline void
+  rethrow_if_nested(const nested_exception& __ex)
+  {
+    __ex.rethrow_nested();
+  }
+
+  // @} group exceptions
+} // namespace std
+
+} // extern "C++"
+
+#endif // __GXX_EXPERIMENTAL_CXX0X__
+
+#pragma GCC visibility pop
+
+#endif // _GLIBCXX_NESTED_EXCEPTION_H