Re: [PATCH] libstdc++: Fix up parallel_backend_serial.h [PR97549]

[Thomas Rodgers via Gcc-patches]

----- Original Message -----
> Hi!
> 
> In GCC 10, parallel_backend.h just included parallel_backend_{serial,tbb}.h
> and
> did nothing beyond that, and parallel_backend_tbb.h provided directly
> namespace __pstl { namespace __par_backend { ... } }
> and defined everything in there, while parallel_backend_serial.h did:
> namespace __pstl { namespace __serial { ... } } and had this
> namespace __pstl { namespace __par_backend { using namespace
> __pstl::__serial; } }
> at the end.
> In GCC 11, parallel_backend.h does:
> namespace __pstl { namespace __par_backend = __serial_backend; }
> after including parallel_backend_serial.h or
> namespace __pstl { namespace __par_backend = __tbb_backend; }
> after including parallel_backend_tbb.h.  The latter then has:
> namespace __pstl { namespace __tbb_backend { ... } }
> and no using etc. at the end, while parallel_backend_serial.h changed to:
> namespace __pstl { namespace __serial_backend { ... } }
> but has this leftover block from the GCC 10 times.  Even changing that
> using namespace __pstl::__serial;
> to
> using namespace __pstl::__serial_backend;
> doesn't work, as it clashes with
> namespace __pstl { namespace __par_backend = __serial_backend; }
> in parallel_backend.h.
> 
> Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux
> both without and with tbb-devel installed.
> 
> Ok for trunk?

Yes, thanks.

> 
> 2021-02-20  Jakub Jelinek  <ja...@redhat.com>
> 
>       PR libstdc++-v3/97549
>       * include/pstl/parallel_backend_serial.h: Remove __pstl::__par_backend.
> 
> --- libstdc++-v3/include/pstl/parallel_backend_serial.h.jj    2020-10-21
> 19:33:24.059872401 +0200
> +++ libstdc++-v3/include/pstl/parallel_backend_serial.h       2021-02-19
> 11:59:56.414645219 +0100
> @@ -127,12 +127,4 @@ __parallel_invoke(_ExecutionPolicy&&, _F
>  } // namespace __serial_backend
>  } // namespace __pstl
>  
> -namespace __pstl
> -{
> -namespace __par_backend
> -{
> -using namespace __pstl::__serial;
> -}
> -} // namespace __pstl
> -
>  #endif /* _PSTL_PARALLEL_BACKEND_SERIAL_H */
> 
>       Jakub
>