Comments addressed. Please find the new diff attached to this e-mail.
Changelog after review comments :
2017-02-18 Dinka Ranns <dinka.ra...@googlemail.com>
C++17 GB50 resolution
* include/std/chrono:
(duration::operator++()): Add _GLIBCXX17_CONSTEXPR.
(duration::operator++(int)): Likewise
(duration::operator--()): Likewise
(duration::operator--(int)): Likewise
(duration::operator+=(const duration&)): Likewise
(duration::operator-=(const duration&)): Likewise
(duration::operator*=(const rep&)): Likewise
(duration::operator/=(const rep&)): Likewise
(duration::operator%=(const rep&)): Likewise
(duration::operator%=(const duration&)): Likewise
(time_point::operator+=(const duration&)): Likewise
(time_point::operator-=(const duration&)): Likewise
* testsuite/20_util/duration/arithmetic/constexpr_c++17.cc: new tests
* testsuite/20_util/time_point/arithmetic/constexpr.cc: new tests
On 15 February 2017 at 09:35, Jonathan Wakely <jwak...@redhat.com> wrote:
> Hi, Dinka, thanks for the patch.
>
> On 14/02/17 21:22 +0000, Dinka Ranns wrote:
>>
>> diff --git a/libstdc++-v3/include/std/chrono
>> b/libstdc++-v3/include/std/chrono
>> index ceae7f8..6a6995c 100644
>> --- a/libstdc++-v3/include/std/chrono
>> +++ b/libstdc++-v3/include/std/chrono
>> @@ -349,50 +349,50 @@ _GLIBCXX_END_NAMESPACE_VERSION
>> operator-() const
>> { return duration(-__r); }
>>
>> - duration&
>> + constexpr duration&
>
>
> This needs to use _GLIBCXX17_CONSTEXPR instead of 'constexpr'
>
> These functions aren't constexpr in C++11 and C++14, and the standard
> (annoyingly) forbids us from adding constexpr anywhere it isn't
> present in the standard.
>
> The macro _GLIBCXX17_CONSTEXPR expands to 'constexpr' if __cplusplus >
> 201402L, and expands to nothing otherwise.
>
> Each new 'constexpr' you've added needs to use that macro.
>
>> diff --git
>> a/libstdc++-v3/testsuite/20_util/duration/arithmetic/constexpr.cc
>> b/libstdc++-v3/testsuite/20_util/duration/arithmetic/constexpr.cc
>> index 285f941..1128a52 100644
>> --- a/libstdc++-v3/testsuite/20_util/duration/arithmetic/constexpr.cc
>> +++ b/libstdc++-v3/testsuite/20_util/duration/arithmetic/constexpr.cc
>> @@ -19,11 +19,31 @@
>>
>> #include <chrono>
>> #include <testsuite_common_types.h>
>
>
> There should be a blank line before and after this function, however
> ...
>
>> +constexpr auto test_operators()
>> +{
>> + std::chrono::nanoseconds d1 { };
>> + d1++;
>
>
> This new function uses C++14 return type deduction, so will fail if
> the test is run in C++11 mode (the default is C++14, but it can be
> overridden on the command-line).
>
>> + ++d1;
>> + d1--;
>> + --d1;
>
>
> Also once you change the new 'constexpr' specifiers to use the
> _GLIBCXX17_CONSTEXPR macro this test will fail in C++14 mode. I think
> this new function needs to be moved to a new test file, such as
> testsuite/20_util/duration/arithmetic/constexpr_c++17.cc
>
> That should contain just your new test_operators() function, because
> the rest of the class will be tested by the existing constexpr.cc test
> file. So something like:
>
> // { dg-options "-std=gnu++17" }
> // { dg-do compile { target c++1z } }
>
> // Copyright etc. etc.
> // ...
>
> #include <chrono>
>
> constexpr auto test_operators()
> {
> // ...
> }
>
> constexpr auto d4 = test_operators();
>
>
> Note that the "dg-do compile" line should use the c++1z target instead
> of c++11, and needs to override the default dialect with a dg-options
> line.
>
> This test doesn't need a "main" function because it's a "dg-do
> compile" test, so isn't linked. (The existing test that you modified
> didn't need one either, but it doesn't do any harm leaving it there).
>
>
>> diff --git
>> a/libstdc++-v3/testsuite/20_util/time_point/arithmetic/constexpr.cc
>> b/libstdc++-v3/testsuite/20_util/time_point/arithmetic/constexpr.cc
>> new file mode 100644
>> index 0000000..e87a226
>> --- /dev/null
>> +++ b/libstdc++-v3/testsuite/20_util/time_point/arithmetic/constexpr.cc
>> @@ -0,0 +1,39 @@
>> +// { dg-do compile { target c++11 } }
>
>
> Since the time_point member functions will only be constexpr in C++17
> this test also needs to use c++1z instead of c++11, and needs to
> override the default C++14 dialect, i.e.
>
> // { dg-options "-std=gnu++17" }
> // { dg-do compile { target c++1z } }
>
diff --git a/libstdc++-v3/include/std/chrono b/libstdc++-v3/include/std/chrono
index 2c33be0..d05eaaf 100644
--- a/libstdc++-v3/include/std/chrono
+++ b/libstdc++-v3/include/std/chrono
@@ -349,50 +349,50 @@ _GLIBCXX_END_NAMESPACE_VERSION
operator-() const
{ return duration(-__r); }
- duration&
+ _GLIBCXX17_CONSTEXPR duration&
operator++()
{
++__r;
return *this;
}
- duration
+ _GLIBCXX17_CONSTEXPR duration
operator++(int)
{ return duration(__r++); }
- duration&
+ _GLIBCXX17_CONSTEXPR duration&
operator--()
{
--__r;
return *this;
}
- duration
+ _GLIBCXX17_CONSTEXPR duration
operator--(int)
{ return duration(__r--); }
- duration&
+ _GLIBCXX17_CONSTEXPR duration&
operator+=(const duration& __d)
{
__r += __d.count();
return *this;
}
- duration&
+ _GLIBCXX17_CONSTEXPR duration&
operator-=(const duration& __d)
{
__r -= __d.count();
return *this;
}
- duration&
+ _GLIBCXX17_CONSTEXPR duration&
operator*=(const rep& __rhs)
{
__r *= __rhs;
return *this;
}
- duration&
+ _GLIBCXX17_CONSTEXPR duration&
operator/=(const rep& __rhs)
{
__r /= __rhs;
@@ -401,7 +401,7 @@ _GLIBCXX_END_NAMESPACE_VERSION
// DR 934.
template<typename _Rep2 = rep>
- typename enable_if<!treat_as_floating_point<_Rep2>::value,
+ _GLIBCXX17_CONSTEXPR typename
enable_if<!treat_as_floating_point<_Rep2>::value,
duration&>::type
operator%=(const rep& __rhs)
{
@@ -410,7 +410,7 @@ _GLIBCXX_END_NAMESPACE_VERSION
}
template<typename _Rep2 = rep>
- typename enable_if<!treat_as_floating_point<_Rep2>::value,
+ _GLIBCXX17_CONSTEXPR typename
enable_if<!treat_as_floating_point<_Rep2>::value,
duration&>::type
operator%=(const duration& __d)
{
@@ -631,14 +631,14 @@ _GLIBCXX_END_NAMESPACE_VERSION
{ return __d; }
// arithmetic
- time_point&
+ _GLIBCXX17_CONSTEXPR time_point&
operator+=(const duration& __dur)
{
__d += __dur;
return *this;
}
- time_point&
+ _GLIBCXX17_CONSTEXPR time_point&
operator-=(const duration& __dur)
{
__d -= __dur;
diff --git
a/libstdc++-v3/testsuite/20_util/duration/arithmetic/constexpr_c++17.cc
b/libstdc++-v3/testsuite/20_util/duration/arithmetic/constexpr_c++17.cc
new file mode 100644
index 0000000..2721765
--- /dev/null
+++ b/libstdc++-v3/testsuite/20_util/duration/arithmetic/constexpr_c++17.cc
@@ -0,0 +1,45 @@
+// { dg-options "-std=gnu++17" }
+// { dg-do compile { target c++1z } }
+
+// Copyright (C) 2011-2017 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/>.
+
+#include <chrono>
+#include <testsuite_common_types.h>
+constexpr auto test_operators()
+{
+ std::chrono::nanoseconds d1 { 1 };
+ d1++;
+ ++d1;
+ d1--;
+ --d1;
+
+ auto d2(d1);
+
+ d1+=d2;
+ d1-=d2;
+
+ d1*=1;
+ d1/=1;
+ d1%=1;
+ d1%=d2;
+
+ return d1;
+}
+
+constexpr auto d4 = test_operators();
+
diff --git a/libstdc++-v3/testsuite/20_util/time_point/arithmetic/constexpr.cc
b/libstdc++-v3/testsuite/20_util/time_point/arithmetic/constexpr.cc
new file mode 100644
index 0000000..2f2aceb
--- /dev/null
+++ b/libstdc++-v3/testsuite/20_util/time_point/arithmetic/constexpr.cc
@@ -0,0 +1,36 @@
+// { dg-options "-std=gnu++17" }
+// { dg-do compile { target c++1z } }
+
+// Copyright (C) 2011-2016 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 <chrono>
+#include <testsuite_common_types.h>
+constexpr auto test_operators()
+{
+ using namespace std::chrono;
+ nanoseconds d1 { };
+ time_point<system_clock> c1 { };
+
+ c1+=d1;
+ c1-=d1;
+
+
+ return 11;
+}
+
+constexpr auto a = test_operators();
