PR libstdc++/68210 adjust operator new and delete for LWG 206

Ensure that nothrow versions of new and delete call the ordinary
versions of new or delete, instead of calling malloc or free directly.

These files are all compiled with -std=gnu++14 so can use noexcept and
nullptr to make the code more readable.

	PR libstdc++/68210
	* doc/xml/manual/intro.xml: Document LWG 206 change.
	* libsupc++/del_op.cc: Replace _GLIBCXX_USE_NOEXCEPT with noexcept.
	* libsupc++/del_opa.cc: Likewise.
	* libsupc++/del_opant.cc: Likewise.
	* libsupc++/del_opnt.cc: Likewise. Call operator delete(ptr) instead
	of free(ptr).
	* libsupc++/del_ops.cc: Replace _GLIBCXX_USE_NOEXCEPT with noexcept.
	* libsupc++/del_opsa.cc: Likewise.
	* libsupc++/del_opva.cc: Likewise.
	* libsupc++/del_opvant.cc: Likewise.
	* libsupc++/del_opvnt.cc: Likewise. Call operator delete[](ptr)
	instead of operator delete(ptr).
	* libsupc++/del_opvs.cc: Replace _GLIBCXX_USE_NOEXCEPT with noexcept.
	* libsupc++/del_opvsa.cc: Likewise.
	* libsupc++/new_op.cc: Use __builtin_expect in check for zero size.
	* libsupc++/new_opa.cc: Use nullptr instead of literal 0.
	* libsupc++/new_opant.cc: Likewise. Replace _GLIBCXX_USE_NOEXCEPT
	with noexcept.
	* libsupc++/new_opnt.cc: Likewise. Call operator new(sz) instead of
	malloc(sz).
	* libsupc++/new_opvant.cc: Use nullptr and noexcept.
	* libsupc++/new_opvnt.cc: Likewise. Call operator new[](sz) instead of
	operator new(sz, nothrow).
	* testsuite/18_support/new_nothrow.cc: New test.

From-SVN: r263478

1 files changed, 183 insertions, 0 deletions

diff --git a/libstdc++-v3/testsuite/18_support/new_nothrow.cc b/libstdc++-v3/testsuite/18_support/new_nothrow.cc
new file mode 100644
index 00000000000..362dabf2bcf
--- /dev/null
+++ b/libstdc++-v3/testsuite/18_support/new_nothrow.cc
@@ -0,0 +1,183 @@
+// Copyright (C) 2018 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-do run }
+
+#include <new>
+#include <stdlib.h>
+#include <testsuite_hooks.h>
+
+// PR libstdc++/68210
+
+struct MyBadAlloc: std::bad_alloc { };
+
+static bool new_fail;
+static bool bad_alloc_thrown;
+static unsigned new_called;
+static unsigned delete_called;
+static unsigned new_vec_called;
+static unsigned delete_vec_called;
+static unsigned new_handler_called;
+
+static void new_handler ()
+{
+    if (new_handler_called++)
+        throw MyBadAlloc ();
+}
+
+void* operator new (size_t n)
+{
+    static size_t cntr;
+
+    ++new_called;
+
+    for ( ; ; ) {
+        if (void *p = new_fail ? 0 : malloc (n + sizeof n)) {
+            *static_cast<size_t*>(p) = ++cntr;
+            return static_cast<size_t*>(p) + 1;
+        }
+
+        if (std::new_handler h = std::set_new_handler (0)) {
+            std::set_new_handler (h);
+            h ();
+        }
+        else {
+            bad_alloc_thrown = true;
+            throw MyBadAlloc ();
+        }
+    }
+}
+
+void operator delete (void *p)
+{
+    ++delete_called;
+    if (p)
+        free (static_cast<size_t*>(p) - 1);
+}
+
+void* operator new[] (size_t n)
+{
+    ++new_vec_called;
+    return operator new(n);
+}
+
+void operator delete[] (void *p)
+{
+    ++delete_vec_called;
+    operator delete(p);
+}
+
+#if __cplusplus >= 201402L
+void operator delete (void *p, std::size_t)
+{
+  ::operator delete(p);
+}
+void operator delete[] (void *p, std::size_t)
+{
+  ::operator delete[](p);
+}
+#endif
+
+void init()
+{
+    new_fail = false;
+    new_called = 0;
+    delete_called = 0;
+    new_vec_called = 0;
+    delete_vec_called = 0;
+    new_handler_called = 0;
+    std::set_new_handler (0);
+}
+
+void
+test01()
+{
+    init ();
+
+    void *p = operator new (1, std::nothrow);
+
+    VERIFY (p != 0);
+    VERIFY (1 == new_called);
+    VERIFY (0 == new_handler_called);
+    VERIFY (!bad_alloc_thrown);
+
+    operator delete (p, std::nothrow);
+    VERIFY( 1 == delete_called );
+
+    new_fail = true;
+    p = operator new (1, std::nothrow);
+
+    VERIFY (0 == p);
+    VERIFY (2 == new_called);
+    VERIFY (0 == new_handler_called);
+    VERIFY (bad_alloc_thrown);
+
+    new_fail = true;
+    bad_alloc_thrown = false;
+    std::set_new_handler (new_handler);
+    p = operator new (1, std::nothrow);
+
+    VERIFY (0 == p);
+    VERIFY (3 == new_called);
+    VERIFY (2 == new_handler_called);
+    VERIFY (!bad_alloc_thrown);
+}
+
+void
+test02()
+{
+    init ();
+
+    void *p = operator new[] (1, std::nothrow);
+
+    VERIFY (p != 0);
+    VERIFY (1 == new_called);
+    VERIFY (1 == new_vec_called);
+    VERIFY (0 == new_handler_called);
+    VERIFY (!bad_alloc_thrown);
+
+    operator delete[] (p, std::nothrow);
+    VERIFY( 1 == delete_called );
+    VERIFY( 1 == delete_vec_called );
+
+    new_fail = true;
+    p = operator new[] (1, std::nothrow);
+
+    VERIFY (0 == p);
+    VERIFY (2 == new_called);
+    VERIFY (2 == new_vec_called);
+    VERIFY (0 == new_handler_called);
+    VERIFY (bad_alloc_thrown);
+
+    new_fail = true;
+    bad_alloc_thrown = false;
+    std::set_new_handler (new_handler);
+    p = operator new[] (1, std::nothrow);
+
+    VERIFY (0 == p);
+    VERIFY (3 == new_called);
+    VERIFY (3 == new_vec_called);
+    VERIFY (2 == new_handler_called);
+    VERIFY (!bad_alloc_thrown);
+}
+
+
+int main()
+{
+  test01();
+  test02();
+}