Fix std::byte namespace declaration

[Jonathan Wakely]

On 23/10/18 07:07 +0200, François Dumont wrote:
>On 10/18/2018 10:34 PM, Jonathan Wakely wrote:
>>On 18/10/18 22:12 +0200, François Dumont wrote:
>>>Current build of libstdc++ with 
>>>--enable-symvers=gnu-versioned-namespace fails (at least under 
>>>Linux) because of:
>>>
>>>In file included from /home/fdt/dev/gcc/build_versioned_ns/x86_64-pc-linux-gnu/libstdc++-v3/include/memory_resource:39,
>>>Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â  from 
>>>../../../../../git/libstdc++-v3/src/c++17/memory_resource.cc:25:
>>>/home/fdt/dev/gcc/build_versioned_ns/x86_64-pc-linux-gnu/libstdc++-v3/include/cstddef:71:59: 
>>>error: la référence à « byte » est ambiguë
>>>Â Â  71 |Â Â  template<> struct __byte_operand<bool> { using __type = 
>>>byte; };
>>>Â Â Â Â Â  | ^~~~
>>>In file included from /home/fdt/dev/gcc/build_versioned_ns/x86_64-pc-linux-gnu/libstdc++-v3/include/bits/stl_algobase.h:61,
>>>Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â  from /home/fdt/dev/gcc/build_versioned_ns/x86_64-pc-linux-gnu/libstdc++-v3/include/memory:62,
>>>Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â  from /home/fdt/dev/gcc/build_versioned_ns/x86_64-pc-linux-gnu/libstdc++-v3/include/memory_resource:37,
>>>Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â  from 
>>>../../../../../git/libstdc++-v3/src/c++17/memory_resource.cc:25:
>>>/home/fdt/dev/gcc/build_versioned_ns/x86_64-pc-linux-gnu/libstdc++-v3/include/bits/cpp_type_traits.h:395:30: 
>>>note: les candidats sont : « enum class std::__8::byte »
>>>Â  395 |Â Â  enum class byte : unsigned char;
>>>Â Â Â Â Â  |Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â  ^~~~
>>>In file included from /home/fdt/dev/gcc/build_versioned_ns/x86_64-pc-linux-gnu/libstdc++-v3/include/memory_resource:39,
>>>Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â  from 
>>>../../../../../git/libstdc++-v3/src/c++17/memory_resource.cc:25:
>>>/home/fdt/dev/gcc/build_versioned_ns/x86_64-pc-linux-gnu/libstdc++-v3/include/cstddef:68:14: 
>>>note:                      « enum class std::byte »
>>>Â Â  68 |Â Â  enum class byte : unsigned char {};
>>>Â Â Â Â Â  |Â Â Â Â Â Â Â Â Â Â Â Â Â  ^~~~
>>>
>>>I think the issue if that std::byte declaration in 
>>>cpp_type_traits.h has been done in versioned namespace, so the 
>>>attached patch.
>>
>>I think the definitions in <cstddef> should use the versioned
>>namespace macros. Then <bits/cpp_type_traits.h> would be correct.
>I thought cstddef was some kind of generated file.
>
>I eventually put all its content in versioned namespace.
>
>Â Â Â  * include/c_global/cstddef: Add versioned namespace.
>
>Build successful with the patch, still tests to run. Ok if successful ?

Yes, OK thanks.