Protect from comma operator overload

Hi

     While working on something else on libstdc++ I started having a 
test failing because of the missing comma overload protection in 
deque.tcc. So I looked for other similar places in the code and here is 
a patch to fix the places I found.

     Let me know if it is still time to commit.

François

On 16 April 2018 at 20:52, François Dumont wrote:
> Hi
>
>     While working on something else on libstdc++ I started having a test
> failing because of the missing comma overload protection in deque.tcc. So I
> looked for other similar places in the code and here is a patch to fix the
> places I found.
>
>     Let me know if it is still time to commit.

The changes look right, but please add new tests to demonstrate the
code that used to fail.

You can use <testsuite_iterators.h> because the iterator types defined
in there have deleted comma operators that should cause errors in
these places.

On 16 April 2018 at 21:08, Jonathan Wakely wrote:
> On 16 April 2018 at 20:52, François Dumont wrote:
>> Hi
>>
>>     While working on something else on libstdc++ I started having a test
>> failing because of the missing comma overload protection in deque.tcc. So I
>> looked for other similar places in the code and here is a patch to fix the
>> places I found.
>>
>>     Let me know if it is still time to commit.
>
> The changes look right, but please add new tests to demonstrate the
> code that used to fail.
>
> You can use <testsuite_iterators.h> because the iterator types defined
> in there have deleted comma operators that should cause errors in
> these places.

Something like this (but in four separate tests):

#include <deque>
#include <list>
#include <vector>
#include <testsuite_iterators.h>

int main()
{
  using namespace __gnu_test;
  int a[1] = {};
  test_container<int, input_iterator_wrapper> t(a, a+1);

  std::deque<int> d;
  d.assign(t.begin(), t.end());

  std::list<int> l;
  l.assign(t.begin(), t.end());

  std::vector<int> v;
  v.assign(t.begin(), t.end());

  std::vector<bool> b;
  b.assign(t.begin(), t.end());
}


Given how rare it is for real code to overload the comma operator, and
that nobody has reported these bugs, I think this can wait for after
GCC 8.

Hi

     Here is the patch I eventually would like to commit.

     Tested under Linux x86_64, ok for trunk ?

François


On 17/04/2018 22:34, François Dumont wrote:
> Yes, I also think there is no rush to fix this issue.
>
> I had already written a test for a different purpose using the 
> input_iterator_wrapper. This is why I detected this std::deque issue.
>
> On 16/04/2018 22:16, Jonathan Wakely wrote:
>> On 16 April 2018 at 21:08, Jonathan Wakely wrote:
>>> On 16 April 2018 at 20:52, François Dumont wrote:
>>>> Hi
>>>>
>>>>      While working on something else on libstdc++ I started having 
>>>> a test
>>>> failing because of the missing comma overload protection in 
>>>> deque.tcc. So I
>>>> looked for other similar places in the code and here is a patch to 
>>>> fix the
>>>> places I found.
>>>>
>>>>      Let me know if it is still time to commit.
>>> The changes look right, but please add new tests to demonstrate the
>>> code that used to fail.
>>>
>>> You can use <testsuite_iterators.h> because the iterator types defined
>>> in there have deleted comma operators that should cause errors in
>>> these places.
>> Something like this (but in four separate tests):
>>
>> #include <deque>
>> #include <list>
>> #include <vector>
>> #include <testsuite_iterators.h>
>>
>> int main()
>> {
>>    using namespace __gnu_test;
>>    int a[1] = {};
>>    test_container<int, input_iterator_wrapper> t(a, a+1);
>>
>>    std::deque<int> d;
>>    d.assign(t.begin(), t.end());
>>
>>    std::list<int> l;
>>    l.assign(t.begin(), t.end());
>>
>>    std::vector<int> v;
>>    v.assign(t.begin(), t.end());
>>
>>    std::vector<bool> b;
>>    b.assign(t.begin(), t.end());
>> }
>>
>>
>> Given how rare it is for real code to overload the comma operator, and
>> that nobody has reported these bugs, I think this can wait for after
>> GCC 8.
>>
>
diff --git a/libstdc++-v3/include/bits/deque.tcc b/libstdc++-v3/include/bits/deque.tcc
index fe96330..1337394 100644
--- a/libstdc++-v3/include/bits/deque.tcc
+++ b/libstdc++-v3/include/bits/deque.tcc
@@ -297,7 +297,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
 		    std::input_iterator_tag)
       {
         iterator __cur = begin();
-        for (; __first != __last && __cur != end(); ++__cur, ++__first)
+        for (; __first != __last && __cur != end(); ++__cur, (void)++__first)
           *__cur = *__first;
         if (__first == __last)
           _M_erase_at_end(__cur);
diff --git a/libstdc++-v3/include/bits/list.tcc b/libstdc++-v3/include/bits/list.tcc
index 22538c9..e90d957 100644
--- a/libstdc++-v3/include/bits/list.tcc
+++ b/libstdc++-v3/include/bits/list.tcc
@@ -312,7 +312,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
         iterator __first1 = begin();
         iterator __last1 = end();
         for (; __first1 != __last1 && __first2 != __last2;
-	     ++__first1, ++__first2)
+	     ++__first1, (void)++__first2)
           *__first1 = *__first2;
         if (__first2 == __last2)
           erase(__first1, __last1);
diff --git a/libstdc++-v3/include/bits/stl_bvector.h b/libstdc++-v3/include/bits/stl_bvector.h
index 05e9ff2..4b52c17 100644
--- a/libstdc++-v3/include/bits/stl_bvector.h
+++ b/libstdc++-v3/include/bits/stl_bvector.h
@@ -1229,7 +1229,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
 		      std::input_iterator_tag)
 	{
 	  iterator __cur = begin();
-	  for (; __first != __last && __cur != end(); ++__cur, ++__first)
+	  for (; __first != __last && __cur != end(); ++__cur, (void)++__first)
 	    *__cur = *__first;
 	  if (__first == __last)
 	    _M_erase_at_end(__cur);
diff --git a/libstdc++-v3/include/bits/vector.tcc b/libstdc++-v3/include/bits/vector.tcc
index 2516e35..f33da03 100644
--- a/libstdc++-v3/include/bits/vector.tcc
+++ b/libstdc++-v3/include/bits/vector.tcc
@@ -273,7 +273,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
       {
 	pointer __cur(this->_M_impl._M_start);
 	for (; __first != __last && __cur != this->_M_impl._M_finish;
-	     ++__cur, ++__first)
+	     ++__cur, (void)++__first)
 	  *__cur = *__first;
 	if (__first == __last)
 	  _M_erase_at_end(__cur);
diff --git a/libstdc++-v3/testsuite/23_containers/deque/modifiers/assign/1.cc b/libstdc++-v3/testsuite/23_containers/deque/modifiers/assign/1.cc
new file mode 100644
index 0000000..fbab09b
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/deque/modifiers/assign/1.cc
@@ -0,0 +1,36 @@
+// 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/>.
+
+#include <deque>
+
+#include <testsuite_iterators.h>
+#include <testsuite_hooks.h>
+
+typedef __gnu_test::test_container<int, __gnu_test::input_iterator_wrapper>
+  input_iterator_seq;
+
+int main()
+{
+  std::deque<int> d;
+
+  int array[] { 0, 1, 2 };
+  input_iterator_seq seq(array, array + 3);
+
+  d.assign(seq.begin(), seq.end());
+  VERIFY( d.size() == 3 );
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/23_containers/list/modifiers/assign/1.cc b/libstdc++-v3/testsuite/23_containers/list/modifiers/assign/1.cc
new file mode 100644
index 0000000..c5fde47
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/list/modifiers/assign/1.cc
@@ -0,0 +1,36 @@
+// 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/>.
+
+#include <list>
+
+#include <testsuite_iterators.h>
+#include <testsuite_hooks.h>
+
+typedef __gnu_test::test_container<int, __gnu_test::input_iterator_wrapper>
+  input_iterator_seq;
+
+int main()
+{
+  std::list<int> l;
+
+  int array[] { 0, 1, 2 };
+  input_iterator_seq seq(array, array + 3);
+
+  l.assign(seq.begin(), seq.end());
+  VERIFY( !l.empty() );
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/23_containers/vector/bool/modifiers/assign/1.cc b/libstdc++-v3/testsuite/23_containers/vector/bool/modifiers/assign/1.cc
new file mode 100644
index 0000000..833201b
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/vector/bool/modifiers/assign/1.cc
@@ -0,0 +1,41 @@
+// 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/>.
+
+#include <vector>
+
+#include <testsuite_iterators.h>
+#include <testsuite_hooks.h>
+
+void test01()
+{
+  typedef __gnu_test::test_container<bool, __gnu_test::input_iterator_wrapper>
+    input_iterator_seq;
+
+  std::vector<bool> bv;
+
+  bool array[] { false, true, true };
+  input_iterator_seq seq(array, array + 3);
+
+  bv.assign(seq.begin(), seq.end());
+  VERIFY( bv.size() == 3 );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/23_containers/vector/modifiers/assign/1.cc b/libstdc++-v3/testsuite/23_containers/vector/modifiers/assign/1.cc
new file mode 100644
index 0000000..ca7b125
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/vector/modifiers/assign/1.cc
@@ -0,0 +1,41 @@
+// 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/>.
+
+#include <vector>
+
+#include <testsuite_iterators.h>
+#include <testsuite_hooks.h>
+
+void test01()
+{
+  typedef __gnu_test::test_container<int, __gnu_test::input_iterator_wrapper>
+    input_iterator_seq;
+
+  std::vector<int> v;
+
+  int array[] { 0, 1, 2 };
+  input_iterator_seq seq(array, array + 3);
+
+  v.assign(seq.begin(), seq.end());
+  VERIFY( v.size() == 3 );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}

On 02/05/18 07:11 +0200, François Dumont wrote:
>Hi
>
>    Here is the patch I eventually would like to commit.
>
>    Tested under Linux x86_64, ok for trunk ?

Ah yes, this is the one I remember thinking would be OK for stage 1.

OK for trunk, thanks.