[PATCH. libstdc++] Use the correct C++14 __cplusplus value (201402L). Added C++1z to the preprocessor.

[PATCH. libstdc++] Use the correct C++14 __cplusplus value (201402L). Added C++1z to the preprocessor.

[Ed Smith-Rowland]

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With revision 214400 we have the C++14 value of __cplusplus set to the 
correct value of 201402L (from 201300L).
We should use this in the std lib headers.  This patch does this.

Also, we've set C++14 value of __cplusplus to 201500L so we can start 
adding post-C++14 library bits with
#if __cplusplus > 201402L
...
#endif

Built and tested clean on x86_64-linux.

OK?


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2014-08-23  Ed Smith-Rowland  <3dw4rd@verizon.net>

	* libsupc++/new: Use the C++14 value of __cplusplus as appropriate.
	* include/bits/parse_numbers.h: Ditto.
	* include/bits/stl_function.h: Ditto.
	* include/bits/unique_ptr.h: Ditto.
	* include/bits/stl_algo.h: Ditto.
	* include/bits/stl_algobase.h: Ditto.
	* include/bits/basic_string.h: Ditto.
	* include/std/complex: Ditto.
	* include/std/iomanip: Ditto.
	* include/std/utility: Ditto.
	* include/std/type_traits: Ditto.
	* include/std/tuple: Ditto.
	* include/std/chrono: Ditto.
	* include/parallel/algobase.h: Ditto.

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Index: libsupc++/new
===================================================================
--- libsupc++/new	(revision 214399)
+++ libsupc++/new	(working copy)
@@ -81,7 +81,7 @@
 
   // We throw this exception for GNU VLAs of negative length in all C++
   // dialects, so declare it if we aren't in strict conformance mode.
-#if __cplusplus > 201103L || !defined(__STRICT_ANSI__)
+#if __cplusplus >= 201402L || !defined(__STRICT_ANSI__)
   class bad_array_length : public bad_alloc
   {
   public:
Index: include/bits/parse_numbers.h
===================================================================
--- include/bits/parse_numbers.h	(revision 214399)
+++ include/bits/parse_numbers.h	(working copy)
@@ -34,7 +34,7 @@
 
 // From n3642.pdf except I added binary literals and digit separator '\''.
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
 
 #include <limits>
 
@@ -283,6 +283,6 @@
 _GLIBCXX_END_NAMESPACE_VERSION
 } // namespace std
 
-#endif // __cplusplus > 201103L
+#endif // __cplusplus >= 201402L
 
 #endif // _GLIBCXX_PARSE_NUMBERS_H
Index: include/bits/stl_function.h
===================================================================
--- include/bits/stl_function.h	(revision 214399)
+++ include/bits/stl_function.h	(working copy)
@@ -56,7 +56,7 @@
 #ifndef _STL_FUNCTION_H
 #define _STL_FUNCTION_H 1
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
 #include <bits/move.h>
 #endif
 
@@ -140,7 +140,7 @@
    *  @{
    */
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   struct __is_transparent;  // undefined
 
   template<typename _Tp = void>
@@ -216,7 +216,7 @@
       { return -__x; }
     };
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   template<>
     struct plus<void>
     {
@@ -311,7 +311,7 @@
    *
    *  @{
    */
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   template<typename _Tp = void>
     struct equal_to;
 
@@ -385,7 +385,7 @@
       { return __x <= __y; }
     };
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   /// One of the @link comparison_functors comparison functors@endlink.
   template<>
     struct equal_to<void>
@@ -481,7 +481,7 @@
    *
    *  @{
    */
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   template<typename _Tp = void>
     struct logical_and;
 
@@ -519,7 +519,7 @@
       { return !__x; }
     };
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   /// One of the @link logical_functors Boolean operations functors@endlink.
   template<>
     struct logical_and<void>
@@ -564,7 +564,7 @@
 #endif
   /** @}  */
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   template<typename _Tp = void>
     struct bit_and;
 
@@ -612,7 +612,7 @@
       { return ~__x; }
     };
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   template <>
     struct bit_and<void>
     {
Index: include/bits/unique_ptr.h
===================================================================
--- include/bits/unique_ptr.h	(revision 214399)
+++ include/bits/unique_ptr.h	(working copy)
@@ -742,7 +742,7 @@
       }
     };
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   template<typename _Tp>
     struct _MakeUniq
     { typedef unique_ptr<_Tp> __single_object; };
Index: include/bits/stl_algo.h
===================================================================
--- include/bits/stl_algo.h	(revision 214399)
+++ include/bits/stl_algo.h	(working copy)
@@ -3570,7 +3570,7 @@
 				   __gnu_cxx::__ops::__iter_comp_iter(__pred));
     }
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   template<typename _ForwardIterator1, typename _ForwardIterator2,
 	   typename _BinaryPredicate>
     bool
Index: include/bits/stl_algobase.h
===================================================================
--- include/bits/stl_algobase.h	(revision 214399)
+++ include/bits/stl_algobase.h	(working copy)
@@ -1090,7 +1090,7 @@
       return true;
     }
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   /**
    *  @brief Tests a range for element-wise equality.
    *  @ingroup non_mutating_algorithms
@@ -1326,7 +1326,7 @@
 	__gnu_cxx::__ops::__iter_comp_iter(__binary_pred));
     }
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
 
   template<typename _InputIterator1, typename _InputIterator2,
 	   typename _BinaryPredicate>
Index: include/bits/basic_string.h
===================================================================
--- include/bits/basic_string.h	(revision 214399)
+++ include/bits/basic_string.h	(working copy)
@@ -3138,7 +3138,7 @@
     { };
 #endif
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
 
   inline namespace literals
   {
@@ -3168,7 +3168,7 @@
   } // inline namespace string_literals
   } // inline namespace literals
 
-#endif // __cplusplus > 201103L
+#endif // __cplusplus >= 201402L
 
 _GLIBCXX_END_NAMESPACE_VERSION
 } // namespace std
Index: include/std/complex
===================================================================
--- include/std/complex	(revision 214399)
+++ include/std/complex	(working copy)
@@ -1924,7 +1924,7 @@
     conj(_Tp __x)
     { return __x; }
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
 
 inline namespace literals {
 inline namespace complex_literals {
Index: include/std/iomanip
===================================================================
--- include/std/iomanip	(revision 214399)
+++ include/std/iomanip	(working copy)
@@ -41,7 +41,7 @@
 
 #if __cplusplus >= 201103L
 #include <locale>
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
 #include <sstream> // used in quoted.
 #endif
 #endif
@@ -337,7 +337,7 @@
       return __os; 
     }
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
 
 _GLIBCXX_END_NAMESPACE_VERSION
   namespace __detail {
@@ -495,7 +495,7 @@
 				__string, __delim, __escape);
     }
 
-#endif // __cplusplus > 201103L
+#endif // __cplusplus >= 201402L
 
 #endif // __cplusplus >= 201103L
 
Index: include/std/utility
===================================================================
--- include/std/utility	(revision 214399)
+++ include/std/utility	(working copy)
@@ -156,7 +156,7 @@
     get(const std::pair<_Tp1, _Tp2>& __in) noexcept
     { return __pair_get<_Int>::__const_get(__in); }
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   template <typename _Tp, typename _Up>
     constexpr _Tp&
     get(pair<_Tp, _Up>& __p) noexcept
@@ -219,7 +219,7 @@
       typedef _Index_tuple<> __type;
     };
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   /// Class template integer_sequence
   template<typename _Tp, _Tp... _Idx>
     struct integer_sequence
Index: include/std/type_traits
===================================================================
--- include/std/type_traits	(revision 214399)
+++ include/std/type_traits	(working copy)
@@ -72,7 +72,7 @@
       typedef _Tp                           value_type;
       typedef integral_constant<_Tp, __v>   type;
       constexpr operator value_type() const { return value; }
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
       constexpr value_type operator()() const { return value; }
 #endif
     };
@@ -1450,7 +1450,7 @@
       add_const<typename add_volatile<_Tp>::type>::type     type;
     };
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   /// Alias template for remove_const
   template<typename _Tp>
     using remove_const_t = typename remove_const<_Tp>::type;
@@ -1519,7 +1519,7 @@
     : public __add_rvalue_reference_helper<_Tp>
     { };
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   /// Alias template for remove_reference
   template<typename _Tp>
     using remove_reference_t = typename remove_reference<_Tp>::type;
@@ -1750,7 +1750,7 @@
   template<>
     struct make_signed<bool>;
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   /// Alias template for make_signed
   template<typename _Tp>
     using make_signed_t = typename make_signed<_Tp>::type;
@@ -1788,7 +1788,7 @@
     struct remove_all_extents<_Tp[]>
     { typedef typename remove_all_extents<_Tp>::type     type; };
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   /// Alias template for remove_extent
   template<typename _Tp>
     using remove_extent_t = typename remove_extent<_Tp>::type;
@@ -1829,7 +1829,7 @@
     : public __add_pointer_helper<_Tp>
     { };
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   /// Alias template for remove_pointer
   template<typename _Tp>
     using remove_pointer_t = typename remove_pointer<_Tp>::type;
@@ -2246,7 +2246,7 @@
       >::type
     { };
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   /// Alias template for aligned_storage
   template<size_t _Len, size_t _Align =
 	    __alignof__(typename __aligned_storage_msa<_Len>::__type)>
Index: include/std/tuple
===================================================================
--- include/std/tuple	(revision 214399)
+++ include/std/tuple	(working copy)
@@ -686,7 +686,7 @@
       typedef typename add_cv<__tuple_element_t<__i, _Tp>>::type type;
     };
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   template<std::size_t __i, typename _Tp>
     using tuple_element_t = typename tuple_element<__i, _Tp>::type;
 #endif
@@ -745,7 +745,7 @@
       return std::forward<__element_type&&>(std::get<__i>(__t));
     }
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   template<typename _Head, size_t __i, typename... _Tail>
     constexpr _Head&
     __get_helper2(_Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
Index: include/std/chrono
===================================================================
--- include/std/chrono	(revision 214399)
+++ include/std/chrono	(working copy)
@@ -780,7 +780,7 @@
   _GLIBCXX_END_NAMESPACE_VERSION
   } // namespace chrono
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
 
   inline namespace literals
   {
@@ -864,7 +864,7 @@
   } // inline namespace chrono_literals
   } // inline namespace literals
 
-#endif // __cplusplus > 201103L
+#endif // __cplusplus >= 201402L
 
   // @} group chrono
 } // namespace std
Index: include/parallel/algobase.h
===================================================================
--- include/parallel/algobase.h	(revision 214399)
+++ include/parallel/algobase.h	(working copy)
@@ -114,7 +114,7 @@
 			       std::__iterator_category(__begin2));
     }
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   // Sequential fallback.
   template<typename _InputIterator1, typename _InputIterator2>
     inline pair<_InputIterator1, _InputIterator2>
@@ -231,7 +231,7 @@
               == __end1;
     }
 
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
   // Sequential fallback
   template<typename _IIter1, typename _IIter2>
     inline bool

Re: [PATCH. libstdc++] Use the correct C++14 __cplusplus value (201402L). Added C++1z to the preprocessor.

[Paolo Carlini]

Hi,

On 08/24/2014 12:37 AM, Ed Smith-Rowland wrote:
> With revision 214400 we have the C++14 value of __cplusplus set to the 
> correct value of 201402L (from 201300L).
It occurs to me: instead of having to remember every time those numbers, 
couldn't we predefine, for example:

     __cplusplus_98
     __cplusplus_11
     __cplusplus_14

with the correct values of course?!?

Thanks,
Paolo.

Re: [PATCH. libstdc++] Use the correct C++14 __cplusplus value (201402L). Added C++1z to the preprocessor.

[Rainer Orth]

Paolo Carlini <paolo.carlini@oracle.com> writes:

> Hi,
>
> On 08/24/2014 12:37 AM, Ed Smith-Rowland wrote:
>> With revision 214400 we have the C++14 value of __cplusplus set to the
>> correct value of 201402L (from 201300L).
> It occurs to me: instead of having to remember every time those numbers,
> couldn't we predefine, for example:
>
>     __cplusplus_98
>     __cplusplus_11
>     __cplusplus_14
>
> with the correct values of course?!?

But won't this lead to portability trouble in the future when people see
those macros and start using them in their own code, breaking
compilation with older or non-g++ compilers?

	Rainer

-- 
-----------------------------------------------------------------------------
Rainer Orth, Center for Biotechnology, Bielefeld University

Re: [PATCH. libstdc++] Use the correct C++14 __cplusplus value (201402L). Added C++1z to the preprocessor.

[Paolo Carlini]

Hi,

On 08/26/2014 10:42 AM, Rainer Orth wrote:
> Paolo Carlini <paolo.carlini@oracle.com> writes:
>
>> Hi,
>>
>> On 08/24/2014 12:37 AM, Ed Smith-Rowland wrote:
>>> With revision 214400 we have the C++14 value of __cplusplus set to the
>>> correct value of 201402L (from 201300L).
>> It occurs to me: instead of having to remember every time those numbers,
>> couldn't we predefine, for example:
>>
>>      __cplusplus_98
>>      __cplusplus_11
>>      __cplusplus_14
>>
>> with the correct values of course?!?
> But won't this lead to portability trouble in the future when people see
> those macros and start using them in their own code, breaking
> compilation with older or non-g++ compilers?
Well, this can happen for any GNU predefined macro... What can I say, I 
tried to help ;) As a last resort we can maybe define the macros in 
bits/c++config...

Paolo.

Re: [PATCH. libstdc++] Use the correct C++14 __cplusplus value (201402L). Added C++1z to the preprocessor.

[Rainer Orth]

Hi Paolo,

> On 08/26/2014 10:42 AM, Rainer Orth wrote:
>> Paolo Carlini <paolo.carlini@oracle.com> writes:
>>
>>> Hi,
>>>
>>> On 08/24/2014 12:37 AM, Ed Smith-Rowland wrote:
>>>> With revision 214400 we have the C++14 value of __cplusplus set to the
>>>> correct value of 201402L (from 201300L).
>>> It occurs to me: instead of having to remember every time those numbers,
>>> couldn't we predefine, for example:
>>>
>>>      __cplusplus_98
>>>      __cplusplus_11
>>>      __cplusplus_14
>>>
>>> with the correct values of course?!?
>> But won't this lead to portability trouble in the future when people see
>> those macros and start using them in their own code, breaking
>> compilation with older or non-g++ compilers?
> Well, this can happen for any GNU predefined macro... What can I say, I

true, but in this case they will be prominent throughout libstdc++
headers.

> tried to help ;) As a last resort we can maybe define the macros in

Greatly appreciated: they are certainly way more mnemonic than the naked
numbers ;-)

> bits/c++config...

Which won't help users seeing them in the headers.  Maybe the issue
could be avoided by chosing names that make it clear that they are
g++/libstdc++ specific, not generic?

Thanks.
        Rainer

-- 
-----------------------------------------------------------------------------
Rainer Orth, Center for Biotechnology, Bielefeld University

Re: [PATCH. libstdc++] Use the correct C++14 __cplusplus value (201402L). Added C++1z to the preprocessor.

[Paolo Carlini]

Hi,

On 08/26/2014 10:56 AM, Rainer Orth wrote:
> bits/c++config...
> Which won't help users seeing them in the headers.  Maybe the issue
> could be avoided by chosing names that make it clear that they are
> g++/libstdc++ specific, not generic?
Sure, whatever works, the names were tentative, for the cpp idea.

Paolo.

Re: [PATCH. libstdc++] Use the correct C++14 __cplusplus value (201402L). Added C++1z to the preprocessor.

[Ed Smith-Rowland]

On 08/26/2014 04:59 AM, Paolo Carlini wrote:
> Hi,
>
> On 08/26/2014 10:56 AM, Rainer Orth wrote:
>> bits/c++config...
>> Which won't help users seeing them in the headers.  Maybe the issue
>> could be avoided by chosing names that make it clear that they are
>> g++/libstdc++ specific, not generic?
> Sure, whatever works, the names were tentative, for the cpp idea.
>
> Paolo.
>
I should have mentioned this thought.

Maybe we could do something more scary like

    __GLIBCXX_CPLUSPLUS_98
    __GLIBCXX_CPLUSPLUS_11
    __GLIBCXX_CPLUSPLUS_14

so people won't use them.

The __cplusplus_11 etc. look almost "standard" ;-)

Ed

Re: [PATCH. libstdc++] Use the correct C++14 __cplusplus value (201402L). Added C++1z to the preprocessor.

[Jonathan Wakely]

On 26/08/14 07:11 -0400, Ed Smith-Rowland wrote:
>On 08/26/2014 04:59 AM, Paolo Carlini wrote:
>>Hi,
>>
>>On 08/26/2014 10:56 AM, Rainer Orth wrote:
>>>bits/c++config...
>>>Which won't help users seeing them in the headers.  Maybe the issue
>>>could be avoided by chosing names that make it clear that they are
>>>g++/libstdc++ specific, not generic?
>>Sure, whatever works, the names were tentative, for the cpp idea.
>>
>>Paolo.
>>
>I should have mentioned this thought.
>
>Maybe we could do something more scary like
>
>   __GLIBCXX_CPLUSPLUS_98
>   __GLIBCXX_CPLUSPLUS_11
>   __GLIBCXX_CPLUSPLUS_14

If they're macros defined by the library they should start with
_GLIBCXX (i.e. a single underscore).

>so people won't use them.
>
>The __cplusplus_11 etc. look almost "standard" ;-)

Agreed.

Re: [PATCH. libstdc++] Use the correct C++14 __cplusplus value (201402L). Added C++1z to the preprocessor.

[Jonathan Wakely]

On 26/08/14 10:28 +0200, Paolo Carlini wrote:
>Hi,
>
>On 08/24/2014 12:37 AM, Ed Smith-Rowland wrote:
>>With revision 214400 we have the C++14 value of __cplusplus set to 
>>the correct value of 201402L (from 201300L).
>It occurs to me: instead of having to remember every time those 
>numbers, couldn't we predefine, for example:
>
>    __cplusplus_98
>    __cplusplus_11
>    __cplusplus_14
>
>with the correct values of course?!?

That seems like a good idea, but I'm not convinced there's any benefit
in Ed's changes to do:

-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L

It seems like unnecessary churn to me, but if someone was changing
every test to use a symbolic constant instead of an integer literal
then I suppose it does no harm to change "> C++11" to ">= C++14" at
the same time.

Re: [PATCH. libstdc++] Use the correct C++14 __cplusplus value (201402L). Added C++1z to the preprocessor.

[Paolo Carlini]

Hi,

On 08/26/2014 10:52 AM, Jonathan Wakely wrote:
> That seems like a good idea, but I'm not convinced there's any benefit
> in Ed's changes to do:
>
> -#if __cplusplus > 201103L
> +#if __cplusplus >= 201402L
>
> It seems like unnecessary churn to me,
about this, I had the same thought ;)

Paolo.

Re: [PATCH. libstdc++] Use the correct C++14 __cplusplus value (201402L). Added C++1z to the preprocessor.

[Paolo Carlini]

Hi again,

On 08/26/2014 10:54 AM, Paolo Carlini wrote:
> Hi,
>
> On 08/26/2014 10:52 AM, Jonathan Wakely wrote:
>> That seems like a good idea, but I'm not convinced there's any benefit
>> in Ed's changes to do:
>>
>> -#if __cplusplus > 201103L
>> +#if __cplusplus >= 201402L
>>
>> It seems like unnecessary churn to me,
> about this, I had the same thought ;)
By the way, in case isn't already clear, it occurs to me that the kind 
of change proposed by Ed, thus standardize on __cplusplus >= "required 
version", will make more sense when the C++17 Standard will be closer. 
So far, since we can simply do everything with only 201103L, my idea too 
of adding _GLIBCXX_CXX11 & co seems quite pointless.

Paolo.

Re: [PATCH. libstdc++] Use the correct C++14 __cplusplus value (201402L). Added C++1z to the preprocessor.

[Ed Smith-Rowland]

On 09/15/2014 05:17 AM, Paolo Carlini wrote:
> Hi again,
>
> On 08/26/2014 10:54 AM, Paolo Carlini wrote:
>> Hi,
>>
>> On 08/26/2014 10:52 AM, Jonathan Wakely wrote:
>>> That seems like a good idea, but I'm not convinced there's any benefit
>>> in Ed's changes to do:
>>>
>>> -#if __cplusplus > 201103L
>>> +#if __cplusplus >= 201402L
>>>
>>> It seems like unnecessary churn to me,
>> about this, I had the same thought ;)
> By the way, in case isn't already clear, it occurs to me that the kind 
> of change proposed by Ed, thus standardize on __cplusplus >= "required 
> version", will make more sense when the C++17 Standard will be closer. 
> So far, since we can simply do everything with only 201103L, my idea 
> too of adding _GLIBCXX_CXX11 & co seems quite pointless.
>
> Paolo.
>
I understand.  I guess I was looking far ahead through the eyes of some 
new maintainer where we have CXX11, CXX14, CXX17, CXX20, ... and after 
the experimental names Cxx0x, Cxx1y had long lost their meaning and 
thinking that these dates and names would be a jumble. As new library 
components come into std:: proper we should look at straightening that 
out and standardizing on something.  For now, one date works well.

The new libraries are safely tucked away in experimental behind
#if __cplusplus <= 201103L
# include <bits/c++14_warning.h>
#else

*** Jonathan: <filesystem> uses:

#if __cplusplus < 201103L
# include <bits/c++0x_warning.h>
#else
and should probably eventually be like the others.

Ed

Re: [PATCH. libstdc++] Use the correct C++14 __cplusplus value (201402L). Added C++1z to the preprocessor.

[Jonathan Wakely]

On 15/09/14 07:15 -0400, Ed Smith-Rowland wrote:
>The new libraries are safely tucked away in experimental behind
>#if __cplusplus <= 201103L
># include <bits/c++14_warning.h>
>#else
>
>*** Jonathan: <filesystem> uses:
>
>#if __cplusplus < 201103L
># include <bits/c++0x_warning.h>
>#else
>and should probably eventually be like the others.

My Filesystem implementation works fine in C++11, I see no reason to
force C++14 usage when it isn't needed.