[PATCH][_GLIBCXX_INLINE_VERSION] Fix std::random_device definition

[François Dumont]

On 28/04/22 11:35, Jonathan Wakely wrote:
> On Thu, 28 Apr 2022 at 05:56, François Dumont via Libstdc++
> <libstdc++@gcc.gnu.org> wrote:
>> Hi
>>
>>       Still time for this fix for gcc 12 ?
> What needs fixing?
>
> std::random_device is already declared in the versioned namespace in
> <bits/random.h>:

Oh, I thought it was necessary because it is what is done in most if not 
all the other sources in src.

I might do a cleanup as part of the patch to adopt the cxx11 abi 
std::string in the _GLIBCXX_INLINE_VERSION mode.


>
> namespace std _GLIBCXX_VISIBILITY(default)
> {
> _GLIBCXX_BEGIN_NAMESPACE_VERSION
> ...
>    /**
>     * A standard interface to a platform-specific non-deterministic
>     * random number generator (if any are available).
>     */
>    class random_device
>    {
>
> So that means the definitions of its member functions will be exported
> as std::__8::random_device::* already, the macros are not needed in
> the src/*/*.cc files.
>
> So it seems to me that the only "problem" is a redundant line in
> config/abi/pre/gnu-versioned-namespace.ver. That line has no effect,
> and can be removed.
>
> I've pushed the attached patch instead.
>
>>       If so I'll make sure to run tests quickly, especially the abi.exp
>> one to confirm that the cleanup in gnu-versioned-namespace.ver do not
>> need to be replaced by the same in __8 namespace.
>>
>> libstdc++: [_GLIBCXX_INLINE_VERSION] Fix std::random_device definition
>>
>> Definition shall be put in _GLIBCXX_BEGIN_VERSION_NAMESPACE/
>> _GLIBCXX_END_VERSION_NAMESPACE like the declaration.
>>
>> libstdc++-v3/ChangeLog
>>
>>       * src/c++11/cow-string-inst.cc: Put random_device member definitions
>>       in versioned namespace.
>>       * src/c++11/random.cc: Likewise.
>>       * config/abi/pre/gnu-versioned-namespace.ver: Remove std::random_device
>>       symbols.
>>
>> François