Re: [committed 03/12] libstdc++: Add macros for the inline namespace std::_V2

["François Dumont" <frs.dumont@gmail.com>]

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Based on what you told me recently maybe this patch is better. It does 
not change the link errors.


On 14/05/22 17:36, François Dumont wrote:
> Versioned namespace does not compile after this patch. With this patch 
> it compiles but does not link because of:
>
> /usr/bin/ld: /usr/bin/ld: DWARF error: can't find .debug_ranges section.
> ../src/c++11/.libs/libc++11convenience.a(chrono.o): in function 
> `std::__8::chrono::system_clock::now()':
> chrono.cc:(.text._ZNSt3__86chrono12system_clock3nowEv+0x0): multiple 
> definition of `std::__8::chrono::system_clock::now()'; /usr/bin/ld: 
> DWARF error: can't find .debug_ranges section.
> .libs/compatibility-chrono.o:compatibility-chrono.cc:(.text._ZNSt3__86chrono12system_clock3nowEv+0x0): 
> first defined here
> /usr/bin/ld: 
> ../src/c++11/.libs/libc++11convenience.a(chrono.o):(.rodata._ZNSt3__86chrono12system_clock9is_steadyE+0x0): 
> multiple definition of `std::__8::chrono::system_clock::is_steady'; 
> .libs/compatibility-chrono.o:(.rodata._ZNSt3__86chrono12system_clock9is_steadyE+0x0): 
> first defined here
> /usr/bin/ld: /usr/bin/ld: DWARF error: can't find .debug_ranges section.
> ../src/c++11/.libs/libc++11convenience.a(system_error.o): in function 
> `std::__8::error_category::default_error_condition(int) const':
> system_error.cc:(.text._ZNKSt3__814error_category23default_error_conditionEi+0x0): 
> multiple definition of 
> `std::__8::error_category::default_error_condition(int) const'; 
> /usr/bin/ld: DWARF error: can't find .debug_ranges section.
> .libs/compatibility-c++0x.o:compatibility-c++0x.cc:(.text._ZNKSt3__814error_category23default_error_conditionEi+0x0): 
> first defined here
> /usr/bin/ld: ../src/c++11/.libs/libc++11convenience.a(system_error.o): 
> in function `std::__8::error_category::equivalent(int, 
> std::__8::error_condition const&) const':
> system_error.cc:(.text._ZNKSt3__814error_category10equivalentEiRKNS_15error_conditionE+0x0): 
> multiple definition of `std::__8::error_category::equivalent(int, 
> std::__8::error_condition const&) const'; 
> .libs/compatibility-c++0x.o:compatibility-c++0x.cc:(.text._ZNKSt3__814error_category10equivalentEiRKNS_15error_conditionE+0x0): 
> first defined here
> /usr/bin/ld: ../src/c++11/.libs/libc++11convenience.a(system_error.o): 
> in function `std::__8::error_category::equivalent(std::__8::error_code 
> const&, int) const':
> system_error.cc:(.text._ZNKSt3__814error_category10equivalentERKNS_10error_codeEi+0x0): 
> multiple definition of 
> `std::__8::error_category::equivalent(std::__8::error_code const&, 
> int) const'; 
> .libs/compatibility-c++0x.o:compatibility-c++0x.cc:(.text._ZNKSt3__814error_category10equivalentERKNS_10error_codeEi+0x0): 
> first defined here
> /usr/bin/ld: ../src/c++11/.libs/libc++11convenience.a(system_error.o): 
> in function `std::__8::error_category::~error_category()':
> system_error.cc:(.text._ZNSt3__814error_categoryD2Ev+0x0): multiple 
> definition of `std::__8::error_category::~error_category()'; 
> .libs/compatibility-c++0x.o:compatibility-c++0x.cc:(.text._ZNSt3__814error_categoryD2Ev+0x0): 
> first defined here
> /usr/bin/ld: ../src/c++11/.libs/libc++11convenience.a(system_error.o): 
> in function `std::__8::error_category::~error_category()':
> system_error.cc:(.text._ZNSt3__814error_categoryD2Ev+0x0): multiple 
> definition of `std::__8::error_category::~error_category()'; 
> .libs/compatibility-c++0x.o:compatibility-c++0x.cc:(.text._ZNSt3__814error_categoryD2Ev+0x0): 
> first defined here
> /usr/bin/ld: ../src/c++11/.libs/libc++11convenience.a(system_error.o): 
> in function `std::__8::error_category::~error_category()':
> system_error.cc:(.text._ZNSt3__814error_categoryD0Ev+0x0): multiple 
> definition of `std::__8::error_category::~error_category()'; 
> .libs/compatibility-c++0x.o:compatibility-c++0x.cc:(.text._ZNSt3__814error_categoryD0Ev+0x0): 
> first defined here
> /usr/bin/ld: ../src/c++11/.libs/libc++11convenience.a(system_error.o): 
> in function `std::__8::system_category()':
> system_error.cc:(.text._ZNSt3__815system_categoryEv+0x0): multiple 
> definition of `std::__8::system_category()'; 
> .libs/compatibility-c++0x.o:compatibility-c++0x.cc:(.text._ZNSt3__815system_categoryEv+0x0): 
> first defined here
> /usr/bin/ld: ../src/c++11/.libs/libc++11convenience.a(system_error.o): 
> in function `std::__8::generic_category()':
> system_error.cc:(.text._ZNSt3__816generic_categoryEv+0x0): multiple 
> definition of `std::__8::generic_category()'; 
> .libs/compatibility-c++0x.o:compatibility-c++0x.cc:(.text._ZNSt3__816generic_categoryEv+0x0): 
> first defined here
>
>
> On 13/05/22 14:40, Jonathan Wakely via Libstdc++ wrote:
>> Tested powerpc64le-linux, pushed to trunk.
>>
>> Unlike the rest of the series, this isn't suitable for backporting
>> because it changes the ABI for the gnu-versioned-namespace build. That's
>> fine for GCC 13, but not OK to change within a release branch, e.g.
>> between 12.1 and 12.2. If we want to backport it, the macro should do
>> the same thing whether or not _GLIBCXX_INLINE_VERSION is set.
>>
>> -- >8 --
>>
>> Use macros to open and close the inline namespace _V2 that is used for
>> ABI versioning of individual components such as chrono::system_clock.
>>
>> This allows the namespace to be hidden in the docs generated by Doxygen,
>> so that we document std::foo instead of std::_V2::foo.
>>
>> This also makes it easy to remove that namespace entirely for the
>> gnu-versioned-namespace build, where everything is already versioned as
>> std::__8 and there are no backwards compatibility guarantees.
>>
>> libstdc++-v3/ChangeLog:
>>
>>     * doc/doxygen/user.cfg.in (PREDEFINED): Expand new macros to
>>     nothing.
>>     * include/bits/c++config (_GLIBCXX_BEGIN_INLINE_ABI_NAMESPACE)
>>     (_GLIBCXX_END_INLINE_ABI_NAMESPACE): Define new macros.
>>     * include/bits/algorithmfwd.h (_V2::__rotate): Use new macros
>>     for the namespace.
>>     * include/bits/chrono.h (chrono::_V2::system_clock): Likewise.
>>     * include/bits/stl_algo.h (_V2::__rotate): Likewise.
>>     * include/std/condition_variable (_V2::condition_variable_any):
>>     Likewise.
>>     * include/std/system_error (_V2::error_category): Likewise.
>> ---
>>   libstdc++-v3/doc/doxygen/user.cfg.in        |  2 ++
>>   libstdc++-v3/include/bits/algorithmfwd.h    | 15 ++++++++-------
>>   libstdc++-v3/include/bits/c++config         | 11 +++++++++--
>>   libstdc++-v3/include/bits/chrono.h          |  4 ++--
>>   libstdc++-v3/include/bits/stl_algo.h        |  5 ++---
>>   libstdc++-v3/include/std/condition_variable |  4 ++--
>>   libstdc++-v3/include/std/system_error       |  5 +++--
>>   7 files changed, 28 insertions(+), 18 deletions(-)
>>
>> diff --git a/libstdc++-v3/doc/doxygen/user.cfg.in 
>> b/libstdc++-v3/doc/doxygen/user.cfg.in
>> index b9babc3993e..2dbed727013 100644
>> --- a/libstdc++-v3/doc/doxygen/user.cfg.in
>> +++ b/libstdc++-v3/doc/doxygen/user.cfg.in
>> @@ -2347,6 +2347,8 @@ PREDEFINED             = __cplusplus=202002L \
>>                            "_GLIBCXX_END_NAMESPACE_CONTAINER= " \
>>                            "_GLIBCXX_END_NAMESPACE_CXX11= " \
>>                            "_GLIBCXX_END_NAMESPACE_LDBL= " \
>> +             "-D_GLIBCXX_BEGIN_INLINE_ABI_NAMESPACE(X)= " \
>> +             "-D_GLIBCXX_END_INLINE_ABI_NAMESPACE(X)= " \
>>                            "_GLIBCXX_TEMPLATE_ARGS=...  " \
>>                            "_GLIBCXX_DEPRECATED= " \
>>                            "_GLIBCXX_DEPRECATED_SUGGEST(E)= " \
>> diff --git a/libstdc++-v3/include/bits/algorithmfwd.h 
>> b/libstdc++-v3/include/bits/algorithmfwd.h
>> index 5271a90b501..aacc34e09e8 100644
>> --- a/libstdc++-v3/include/bits/algorithmfwd.h
>> +++ b/libstdc++-v3/include/bits/algorithmfwd.h
>> @@ -601,13 +601,14 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>>       _OIter
>>       reverse_copy(_BIter, _BIter, _OIter);
>>   -  inline namespace _V2
>> -  {
>> -    template<typename _FIter>
>> -      _GLIBCXX20_CONSTEXPR
>> -      _FIter
>> -      rotate(_FIter, _FIter, _FIter);
>> -  }
>> +_GLIBCXX_BEGIN_INLINE_ABI_NAMESPACE(_V2)
>> +
>> +  template<typename _FIter>
>> +    _GLIBCXX20_CONSTEXPR
>> +    _FIter
>> +    rotate(_FIter, _FIter, _FIter);
>> +
>> +_GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
>>       template<typename _FIter, typename _OIter>
>>       _GLIBCXX20_CONSTEXPR
>> diff --git a/libstdc++-v3/include/bits/c++config 
>> b/libstdc++-v3/include/bits/c++config
>> index 2798b9786dc..150b0bc5834 100644
>> --- a/libstdc++-v3/include/bits/c++config
>> +++ b/libstdc++-v3/include/bits/c++config
>> @@ -345,13 +345,16 @@ namespace __gnu_cxx
>>   # define _GLIBCXX_DEFAULT_ABI_TAG
>>   #endif
>>   -// Defined if inline namespaces are used for versioning.
>> +// Non-zero if inline namespaces are used for versioning the entire 
>> library.
>>   #define _GLIBCXX_INLINE_VERSION
>>   -// Inline namespace for symbol versioning.
>>   #if _GLIBCXX_INLINE_VERSION
>> +// Inline namespace for symbol versioning of (nearly) everything in 
>> std.
>>   # define _GLIBCXX_BEGIN_NAMESPACE_VERSION namespace __8 {
>>   # define _GLIBCXX_END_NAMESPACE_VERSION }
>> +// Unused when everything in std is versioned anyway.
>> +# define _GLIBCXX_BEGIN_INLINE_ABI_NAMESPACE(X)
>> +# define _GLIBCXX_END_INLINE_ABI_NAMESPACE(X)
>>     namespace std
>>   {
>> @@ -376,8 +379,12 @@ _GLIBCXX_END_NAMESPACE_VERSION
>>   }
>>     #else
>> +// Unused.
>>   # define _GLIBCXX_BEGIN_NAMESPACE_VERSION
>>   # define _GLIBCXX_END_NAMESPACE_VERSION
>> +// Used to version individual components, e.g. 
>> std::_V2::error_category.
>> +# define _GLIBCXX_BEGIN_INLINE_ABI_NAMESPACE(X) inline namespace X {
>> +# define _GLIBCXX_END_INLINE_ABI_NAMESPACE(X)   } // inline namespace X
>>   #endif
>>     // Inline namespaces for special modes: debug, parallel.
>> diff --git a/libstdc++-v3/include/bits/chrono.h 
>> b/libstdc++-v3/include/bits/chrono.h
>> index 421898516ae..745f9a81357 100644
>> --- a/libstdc++-v3/include/bits/chrono.h
>> +++ b/libstdc++-v3/include/bits/chrono.h
>> @@ -1099,7 +1099,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>>       // compatibility definitions for previous versions.  At some
>>       // point, when these clocks settle down, the inlined namespaces
>>       // can be removed.  XXX GLIBCXX_ABI Deprecated
>> -    inline namespace _V2 {
>> +_GLIBCXX_BEGIN_INLINE_ABI_NAMESPACE(_V2)
>>         /**
>>        *  @brief System clock.
>> @@ -1171,7 +1171,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>>       */
>>       using high_resolution_clock = system_clock;
>>   -    } // end inline namespace _V2
>> +_GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
>>     #if __cplusplus >= 202002L
>>       /// @addtogroup chrono
>> diff --git a/libstdc++-v3/include/bits/stl_algo.h 
>> b/libstdc++-v3/include/bits/stl_algo.h
>> index 1f07b9e6589..6619ff7bf1d 100644
>> --- a/libstdc++-v3/include/bits/stl_algo.h
>> +++ b/libstdc++-v3/include/bits/stl_algo.h
>> @@ -1190,8 +1190,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>>         return __m;
>>       }
>>   -  inline namespace _V2
>> -  {
>> +_GLIBCXX_BEGIN_INLINE_ABI_NAMESPACE(_V2)
>>       /// This is a helper function for the rotate algorithm.
>>     template<typename _ForwardIterator>
>> @@ -1398,7 +1397,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>>                  std::__iterator_category(__first));
>>       }
>>   -  } // namespace _V2
>> +_GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
>>       /**
>>      *  @brief Copy a sequence, rotating its elements.
>> diff --git a/libstdc++-v3/include/std/condition_variable 
>> b/libstdc++-v3/include/std/condition_variable
>> index 2a23e65bbd3..06c4ff9ebdd 100644
>> --- a/libstdc++-v3/include/std/condition_variable
>> +++ b/libstdc++-v3/include/std/condition_variable
>> @@ -234,7 +234,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>>       void (*_M_cb)(void*);
>>     };
>>   -  inline namespace _V2 {
>> +_GLIBCXX_BEGIN_INLINE_ABI_NAMESPACE(_V2)
>>       /// condition_variable_any
>>     // Like above, but mutex is not required to have try_lock.
>> @@ -439,7 +439,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>>   #endif
>>     };
>>   -  } // end inline namespace
>> +_GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
>>       /// @} group condition_variables
>>   _GLIBCXX_END_NAMESPACE_VERSION
>> diff --git a/libstdc++-v3/include/std/system_error 
>> b/libstdc++-v3/include/std/system_error
>> index 45a1d283556..dcef94e16e2 100644
>> --- a/libstdc++-v3/include/std/system_error
>> +++ b/libstdc++-v3/include/std/system_error
>> @@ -77,7 +77,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>>   #endif // C++17
>>     /// @}
>>   -  inline namespace _V2 {
>> +_GLIBCXX_BEGIN_INLINE_ABI_NAMESPACE(_V2)
>>       /** @addtogroup diagnostics
>>      * @{
>> @@ -168,7 +168,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>>     _GLIBCXX_CONST const error_category& system_category() noexcept;
>>       /// @}
>> -  } // end inline namespace
>> +
>> +_GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
>>       /** @addtogroup diagnostics
>>      * @{
>

[-- Attachment #2: fix_version_namespace_build2.patch --]
[-- Type: text/x-patch, Size: 1780 bytes --]

diff --git a/libstdc++-v3/src/c++11/chrono.cc b/libstdc++-v3/src/c++11/chrono.cc
index 6825b5bc4bf..e52211d9aab 100644
--- a/libstdc++-v3/src/c++11/chrono.cc
+++ b/libstdc++-v3/src/c++11/chrono.cc
@@ -39,13 +39,8 @@
 
 namespace std _GLIBCXX_VISIBILITY(default)
 {
-_GLIBCXX_BEGIN_NAMESPACE_VERSION
-
   namespace chrono
   {
-    // XXX GLIBCXX_ABI Deprecated
-    inline namespace _V2 {
-
     constexpr bool system_clock::is_steady;
 
     system_clock::time_point
@@ -93,9 +88,5 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       return time_point(system_clock::now().time_since_epoch());
 #endif
     }
-
-  } // end inline namespace _V2
   } // namespace chrono
-
-_GLIBCXX_END_NAMESPACE_VERSION
 } // namespace std
diff --git a/libstdc++-v3/src/c++11/system_error.cc b/libstdc++-v3/src/c++11/system_error.cc
index 7b1a5a20637..cc2c491cdbb 100644
--- a/libstdc++-v3/src/c++11/system_error.cc
+++ b/libstdc++-v3/src/c++11/system_error.cc
@@ -516,8 +516,6 @@ namespace
 
 namespace std _GLIBCXX_VISIBILITY(default)
 {
-_GLIBCXX_BEGIN_NAMESPACE_VERSION
-
   void
   __throw_system_error(int __i __attribute__((unused)))
   {
@@ -527,10 +525,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
   error_category::~error_category() = default;
 
   const error_category&
-  _V2::system_category() noexcept { return system_category_instance.obj; }
+  system_category() noexcept { return system_category_instance.obj; }
 
   const error_category&
-  _V2::generic_category() noexcept { return generic_category_instance.obj; }
+  generic_category() noexcept { return generic_category_instance.obj; }
 
   system_error::~system_error() = default;
 
@@ -560,6 +558,4 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     return {msg.c_str(), msg.length()};
   }
 #endif
-
-_GLIBCXX_END_NAMESPACE_VERSION
 } // namespace