Re: [PATCH v2] count: Switch from GCC to C11 thread-local storage

[Akira Yokosawa <akiyks@gmail.com>]

Hi Elad,

On Wed, 17 Aug 2022 07:00:50 -0400, Elad Lahav wrote:
> Signed-off-by: Elad Lahav <e2lahav@gmail.com>
> ---

As there is no changelog here, let me ask a (maybe stupid) question.

What is your goal of diverting from GCC extensions and switching
to the C11 standard?

Do you want the codebase under CodeSamples/ to be strictly
conformant to C11 or later?

Runnig "make" under CodeSamples/count, with "-std=c11" appended
to GCC_ARGS, I get a lot of compile errors/warnings (with GCC 9.4.0
under Ubuntu 20.04), beginning with:

    cc -g -O2 -Wall -std=c11  -o count_atomic count_atomic.c -lpthread

    In file included from /usr/include/sched.h:34,

                     from /usr/include/pthread.h:22,

                     from ../api.h:159,

                     from count_atomic.c:22:

    /usr/include/time.h:113:5: error: unknown type name 'locale_t'

      113 |     locale_t __loc) __THROW;

          |     ^~~~~~~~


A workaround is to append "-D_GNU_SOURCE" to GCC_ARGS.  With that,
I get the next warning of:

    ../api.h:766:2: warning: implicit declaration of function 'typeof' [-Wimplicit-function-declaration]

  766 |  typeof(*ptr) _____actual = (o); \


Apparently, typeof() is another GCC extension.  __typeof__() might
be used instead, but it is not ISO C.

So what is you goal of these switches?

        Thanks, Akira

>  CodeSamples/count/count_end.c | 12 ++++++------
>  count/count.tex               | 20 ++++++++++++--------
>  2 files changed, 18 insertions(+), 14 deletions(-)
> 
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