PR libstdc++/80624 satisfy invariant for char_traits<char16_t>::eof()

	PR libstdc++/80624
	* doc/xml/manual/status_cxx2011.xml: Document to_int_type behaviour.
	* include/bits/char_traits.h (char_traits<char16_t>::to_int_type):
	Transform eof value to U+FFFD.
	* testsuite/21_strings/char_traits/requirements/char16_t/eof.cc: New.
	* testsuite/27_io/basic_streambuf/sgetc/char16_t/80624.cc: New.
	* testsuite/27_io/basic_streambuf/sputc/char16_t/80624.cc: New.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@248843 138bc75d-0d04-0410-961f-82ee72b054a4

2 files changed, 115 insertions, 0 deletions

diff --git a/libstdc++-v3/testsuite/27_io/basic_streambuf/sgetc/char16_t/80624.cc b/libstdc++-v3/testsuite/27_io/basic_streambuf/sgetc/char16_t/80624.cc
new file mode 100644
index 00000000000..c08c2274706
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_streambuf/sgetc/char16_t/80624.cc
@@ -0,0 +1,56 @@
+// Copyright (C) 2017 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 { target c++11 } }
+
+#include <streambuf>
+#include <testsuite_hooks.h>
+
+struct streambuf : std::basic_streambuf<char16_t>
+{
+  basic_streambuf* setbuf(char_type* s, std::streamsize n) override
+  {
+    setp(s, s + n);
+    setg(s, s, s + n);
+    return this;
+  }
+};
+
+void
+test01()
+{
+  using traits = streambuf::traits_type;
+
+  char16_t buf[2] = { streambuf::char_type(-1), streambuf::char_type(-2) };
+  streambuf sb;
+  sb.pubsetbuf(buf, 2);
+
+  streambuf::int_type res;
+
+  res = sb.sbumpc();
+  VERIFY( traits::eq_int_type(res, traits::eof()) == false );
+  res = sb.sbumpc();
+  VERIFY( traits::eq_int_type(res, traits::eof()) == false );
+  res = sb.sbumpc();
+  VERIFY( traits::eq_int_type(res, traits::eof()) == true );
+}
+
+int
+main()
+{
+  test01();
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_streambuf/sputc/char16_t/80624.cc b/libstdc++-v3/testsuite/27_io/basic_streambuf/sputc/char16_t/80624.cc
new file mode 100644
index 00000000000..a2a19176514
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_streambuf/sputc/char16_t/80624.cc
@@ -0,0 +1,59 @@
+// Copyright (C) 2017 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 { target c++11 } }
+
+#include <streambuf>
+#include <testsuite_hooks.h>
+
+struct streambuf : std::basic_streambuf<char16_t>
+{
+  basic_streambuf* setbuf(char_type* s, std::streamsize n) override
+  {
+    setp(s, s + n);
+    setg(s, s, s + n);
+    return this;
+  }
+};
+
+void
+test01()
+{
+  using traits = streambuf::traits_type;
+
+  char16_t buf[2] = { };
+  streambuf sb;
+  sb.pubsetbuf(buf, 2);
+
+  streambuf::int_type res;
+
+  res = sb.sputc(streambuf::char_type(-1));
+  VERIFY( traits::eq_int_type(res, traits::eof()) == false );
+  res = sb.sputc(streambuf::char_type(-2));
+  VERIFY( traits::eq_int_type(res, traits::eof()) == false );
+  res = sb.sputc(streambuf::char_type(1));
+  VERIFY( traits::eq_int_type(res, traits::eof()) == true );
+
+  VERIFY( buf[0] == streambuf::char_type(-1) );
+  VERIFY( buf[1] == streambuf::char_type(-2) );
+}
+
+int
+main()
+{
+  test01();
+}