obtained gcc-4.6.4.tar.bz2 from upstream website;upstream

verified gcc-4.6.4.tar.bz2.sig;
imported gcc-4.6.4 source tree from verified upstream tarball.

downloading a git-generated archive based on the 'upstream' tag
should provide you with a source tree that is binary identical
to the one extracted from the above tarball.

if you have obtained the source via the command 'git clone',
however, do note that line-endings of files in your working
directory might differ from line-endings of the respective
files in the upstream repository.

7 files changed, 583 insertions, 0 deletions

diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/1-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/1-in.cc
new file mode 100644
index 000000000..f8190a9cd
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/1-in.cc
@@ -0,0 +1,93 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 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/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetc.txt"; // file with data in it
+
+// Test overloaded virtual functions.
+void test01() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef std::filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 		traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2, c3;
+
+  // int_type sputbackc(char_type c)
+  // if in_cur not avail || ! traits::eq(c, gptr() [-1]), return pbfail
+  // otherwise decrements in_cur and returns *gptr()
+
+  // in
+  {
+    constraint_filebuf fb_01; // in 
+    fb_01.open(name_01, ios::in);
+    VERIFY( !fb_01.write_position() );
+    c1 = fb_01.sbumpc();
+    VERIFY( c1 == '/' );
+    c2 = fb_01.sputbackc('/');
+    VERIFY( c1 == c2 );
+    c3 = fb_01.sgetc();
+    VERIFY( c3 == c2 );
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == c2 );
+    fb_01.sbumpc();
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == ' ' );
+    c1 = fb_01.sgetc();
+    c2 = fb_01.sputbackc('a');
+    VERIFY( c2 == 'a' );
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == c2 );
+    c3 = fb_01.sgetc();
+    VERIFY( c1 == c3 );
+    fb_01.pubseekoff(5, ios_base::beg, ios_base::in);
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == '0' );
+    fb_01.sbumpc();
+    c1 = fb_01.sbumpc();
+    VERIFY( c1 == '1' );
+    c2 = fb_01.sputbackc('b');
+    VERIFY( c2 == 'b' );
+    fb_01.sbumpc();
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == '1' );
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == '7' );
+    VERIFY( !fb_01.write_position() );
+    VERIFY( fb_01.read_position() );
+  }
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/1-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/1-io.cc
new file mode 100644
index 000000000..726947379
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/1-io.cc
@@ -0,0 +1,103 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 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/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "tmp_sputbackc_1io.tst"; // empty file, need to create
+
+void test01() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+  typedef size_t 			size_type;
+
+  bool test __attribute__((unused)) = true;
+  streamsize 			strmsz_1, strmsz_2;
+  int_type 			c1, c2, c3;
+
+  // int_type sputbackc(char_type c)
+  // if in_cur not avail || ! traits::eq(c, gptr() [-1]), return pbfail
+  // otherwise decrements in_cur and returns *gptr()
+
+  // in | out
+  {
+    constraint_filebuf fb_01; 
+    fb_01.open(name_01, ios_base::out | ios_base::in | ios_base::trunc);
+    VERIFY( !fb_01.write_position() );
+    VERIFY( !fb_01.read_position() );
+    strmsz_1 = fb_01.sputn("racadabras", 10);//"abracadabras or what?"
+    strmsz_2 = fb_01.sputn(", i wanna reach out and", 10);
+    fb_01.pubseekoff(0, std::ios_base::cur);
+    c1 = fb_01.sgetc(); // -1
+    c2 = fb_01.sputbackc('z');
+    strmsz_2 = fb_01.in_avail();
+    c3 = fb_01.sgetc();
+    VERIFY( c3 == c2 );
+    VERIFY( c1 != c3 );
+    VERIFY( 1 == strmsz_2 );
+    //test for _in_cur == _in_beg
+    // fb_01._M_out_beg = "bd23456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZracada" etc
+    fb_01.pubseekoff(10, std::ios_base::beg);
+    fb_01.sputc('m');
+    fb_01.pubseekoff(0, std::ios_base::cur);
+    strmsz_1 = fb_01.in_avail(); 
+    c1 = fb_01.sgetc(); 
+    fb_01.snextc();
+    c2 = fb_01.sputbackc('z');  
+    strmsz_2 = fb_01.in_avail(); 
+    c3 = fb_01.sgetc();  
+    VERIFY( c1 != c2 );
+    VERIFY( c3 == c2 );
+    VERIFY( c1 != c3 );
+    VERIFY( c2 == 'z' );
+    // test for replacing char with identical one
+    fb_01.snextc();
+    fb_01.pubseekoff(0, std::ios_base::cur);
+    fb_01.sputc('u');
+    fb_01.sputc('v');
+    fb_01.sputc('a');
+    fb_01.pubseekoff(0, std::ios_base::end);
+    strmsz_1 = fb_01.in_avail();
+    c2 = fb_01.sputbackc('a');
+    strmsz_2 = fb_01.in_avail();
+    c3 = fb_01.sgetc();
+    VERIFY( c3 == c2 );
+    VERIFY( strmsz_1 + 1 == strmsz_2 );
+    VERIFY( !fb_01.write_position() );
+    VERIFY( fb_01.read_position() );
+  }
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/1-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/1-out.cc
new file mode 100644
index 000000000..2cd1fdfef
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/1-out.cc
@@ -0,0 +1,71 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 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/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "tmp_sputbackc_1out.tst"; // empty file, need to create
+
+// Test overloaded virtual functions.
+void test01() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef std::filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 		traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2;
+
+  // int_type sputbackc(char_type c)
+  // if in_cur not avail || ! traits::eq(c, gptr() [-1]), return pbfail
+  // otherwise decrements in_cur and returns *gptr()
+
+  // out
+  {
+    constraint_filebuf fb_01; // out
+    fb_01.open(name_01, ios::out | ios::trunc);    
+    VERIFY( !fb_01.write_position() );
+    VERIFY( !fb_01.read_position() );
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == traits_type::eof() );
+    c2 = fb_01.sputbackc('a');
+    VERIFY( c2 == traits_type::eof() );
+    fb_01.sbumpc();
+    c1 = fb_01.sbumpc();
+    c2 = fb_01.sputbackc('a');
+    VERIFY( c1 == c2 );
+    VERIFY( !fb_01.write_position() );
+    VERIFY( !fb_01.read_position() );
+  }
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/2-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/2-in.cc
new file mode 100644
index 000000000..a2aa792e8
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/2-in.cc
@@ -0,0 +1,93 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 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/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetc.txt"; // file with data in it
+
+// Test overloaded virtual functions.
+void test01() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef std::filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 		traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2, c3;
+
+  // int_type sputbackc(char_type c)
+  // if in_cur not avail || ! traits::eq(c, gptr() [-1]), return pbfail
+  // otherwise decrements in_cur and returns *gptr()
+
+  // in
+  {
+    constraint_filebuf fb_01; // in 
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios::in);
+    VERIFY( fb_01.unbuffered() );
+    c1 = fb_01.sbumpc();
+    VERIFY( c1 == '/' );
+    c2 = fb_01.sputbackc('/');
+    VERIFY( c1 == c2 );
+    c3 = fb_01.sgetc();
+    VERIFY( c3 == c2 );
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == c2 );
+    fb_01.sbumpc();
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == ' ' );
+    c1 = fb_01.sgetc();
+    c2 = fb_01.sputbackc('a');
+    VERIFY( c2 == 'a' );
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == c2 );
+    c3 = fb_01.sgetc();
+    VERIFY( c1 == c3 );
+    fb_01.pubseekoff(5, ios_base::beg, ios_base::in);
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == '0' );
+    fb_01.sbumpc();
+    c1 = fb_01.sbumpc();
+    VERIFY( c1 == '1' );
+    c2 = fb_01.sputbackc('b');
+    VERIFY( c2 == 'b' );
+    fb_01.sbumpc();
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == '1' );
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == '7' );
+    VERIFY( fb_01.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/2-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/2-io.cc
new file mode 100644
index 000000000..588c6b9b7
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/2-io.cc
@@ -0,0 +1,102 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 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/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "tmp_sputbackc_2io.tst"; // empty file, need to create
+
+void test01() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+  typedef size_t 			size_type;
+
+  bool test __attribute__((unused)) = true;
+  streamsize 			strmsz_1, strmsz_2;
+  int_type 			c1, c2, c3;
+
+  // int_type sputbackc(char_type c)
+  // if in_cur not avail || ! traits::eq(c, gptr() [-1]), return pbfail
+  // otherwise decrements in_cur and returns *gptr()
+
+  // in | out
+  {
+    constraint_filebuf fb_01;
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios_base::out | ios_base::in | ios_base::trunc);
+    VERIFY( fb_01.unbuffered() );
+    strmsz_1 = fb_01.sputn("racadabras", 10);//"abracadabras or what?"
+    strmsz_2 = fb_01.sputn(", i wanna reach out and", 10);
+    fb_01.pubseekoff(0, std::ios_base::cur);
+    c1 = fb_01.sgetc(); // -1
+    c2 = fb_01.sputbackc('z');
+    strmsz_2 = fb_01.in_avail();
+    c3 = fb_01.sgetc();
+    VERIFY( c3 == c2 );
+    VERIFY( c1 != c3 );
+    VERIFY( 1 == strmsz_2 );
+    //test for _in_cur == _in_beg
+    // fb_01._M_out_beg = "bd23456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZracada" etc
+    fb_01.pubseekoff(10, std::ios_base::beg);
+    fb_01.sputc('m');
+    fb_01.pubseekoff(0, std::ios_base::cur);
+    strmsz_1 = fb_01.in_avail(); 
+    c1 = fb_01.sgetc(); 
+    fb_01.snextc();
+    c2 = fb_01.sputbackc('z');  
+    strmsz_2 = fb_01.in_avail(); 
+    c3 = fb_01.sgetc();  
+    VERIFY( c1 != c2 );
+    VERIFY( c3 == c2 );
+    VERIFY( c1 != c3 );
+    VERIFY( c2 == 'z' );
+    // test for replacing char with identical one
+    fb_01.snextc();
+    fb_01.pubseekoff(0, std::ios_base::cur);
+    fb_01.sputc('u');
+    fb_01.sputc('v');
+    fb_01.sputc('a');
+    fb_01.pubseekoff(0, std::ios_base::end);
+    strmsz_1 = fb_01.in_avail();
+    c2 = fb_01.sputbackc('a');
+    strmsz_2 = fb_01.in_avail();
+    c3 = fb_01.sgetc();
+    VERIFY( c3 == c2 );
+    VERIFY( strmsz_1 + 1 == strmsz_2 );
+    VERIFY( fb_01.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/2-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/2-out.cc
new file mode 100644
index 000000000..f72ef3b67
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/2-out.cc
@@ -0,0 +1,72 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 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/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "tmp_sputbackc_2out.tst"; // empty file, need to create
+
+// Test overloaded virtual functions.
+void test01() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef std::filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 		traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2;
+
+  // int_type sputbackc(char_type c)
+  // if in_cur not avail || ! traits::eq(c, gptr() [-1]), return pbfail
+  // otherwise decrements in_cur and returns *gptr()
+
+  // out
+  {
+    constraint_filebuf fb_01; // out
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios::out | ios::trunc);    
+    VERIFY( fb_01.unbuffered() );
+    VERIFY( !fb_01.read_position() );
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == traits_type::eof() );
+    c2 = fb_01.sputbackc('a');
+    VERIFY( c2 == traits_type::eof() );
+    fb_01.sbumpc();
+    c1 = fb_01.sbumpc();
+    c2 = fb_01.sputbackc('a');
+    VERIFY( c1 == c2 );
+    VERIFY( fb_01.unbuffered() );
+    VERIFY( !fb_01.read_position() );
+  }
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/9425.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/9425.cc
new file mode 100644
index 000000000..608f13260
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/9425.cc
@@ -0,0 +1,49 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 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/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+
+// libstdc++/9439, libstdc++/9425
+// basic_filebuf<>::pbackfail calls basic_filebuf<>::seekoff, but
+// fails to check the return value
+void test09()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  filebuf fbuf;
+  fbuf.open(name_01, ios_base::in);
+  filebuf::int_type r = fbuf.sputbackc('a');
+  fbuf.close();
+
+  VERIFY( r == filebuf::traits_type::eof() );
+}
+
+int main() 
+{
+  test09();
+  return 0;
+}