Re: [PATCH RESEND] Check whether pthread_sigmask is a simple macro

[Pádraig Brady]

On 01/06/15 07:43, Pavel Fedin wrote:
>  GNULib's pthread_sigmask() is configured and builds incorrectly on MinGW64. 
> Configure
> script detects it as
> present, and this is technically correct, but:
> --- cut ---
> /* Windows has rudimentary signals support.  */
> #define pthread_sigmask(H, S1, S2) 0
> --- cut ---
>  (see
> http://sourceforge.net/p/mingw-w64/mingw-w64/ci/master/tree/mingw-w64-libraries/winpthread
> s/include/pthread_signal.h)
> 
>  And this causes failure building gnulib's pthread_sigmask.c, because it 
> tries to refer to
> original pthread_sigmask() after #undef'ing it.
>  This patch recognizes that pthread_sigmask is a simple macro and there's no 
> real function
> behind it, and in this case it produces the following settings:
> HAVE_PTHREAD_SIGMASK=0
> LIB_PTHREAD_SIGMASK=''
> REPLACE_PTHREAD_SIGMASK=1
>  so that pthread_sigmask() is entirely emulated by GNULib.
> 
>  Related topic: 
> http://lists.gnu.org/archive/html/bug-gnulib/2015-04/msg00065.html
> 
> Signed-off-by: Pavel Fedin <address@hidden>
> 
> m4/pthread_sigmask.m4 | 24 ++++++++++++++++++++++++
>  1 file changed, 24 insertions(+)
> 
> diff --git a/m4/pthread_sigmask.m4 b/m4/pthread_sigmask.m4
> index 5c17dfc..a974848 100644
> --- a/m4/pthread_sigmask.m4
> +++ b/m4/pthread_sigmask.m4
> @@ -40,6 +40,30 @@ AC_DEFUN([gl_FUNC_PTHREAD_SIGMASK],
>               LIBS="$gl_save_LIBS"
>              ])
>            if test $gl_cv_func_pthread_sigmask_in_LIBMULTITHREAD = yes; then
> +            AC_CACHE_CHECK([whether pthread_sigmask is only a macro],
> +              [gl_cv_func_pthread_sigmask_is_macro],
> +              [gl_save_LIBS="$LIBS"
> +               LIBS="$LIBS $LIBMULTITHREAD"
> +               AC_LINK_IFELSE(
> +                 [AC_LANG_PROGRAM(
> +                    [[#include <pthread.h>
> +                      #include <signal.h>

> +                      #undef pthread_sigmask
> +                    ]],
> +                    [[return pthread_sigmask (0, (sigset_t *) 0, (sigset_t 
> *) 0);]])
> +                 ],
> +                 [gl_cv_func_pthread_sigmask_is_macro=no],
> +                 [gl_cv_func_pthread_sigmask_is_macro=yes])
> +               LIBS="$gl_save_LIBS"
> +              ])
> +            if test $gl_cv_func_pthread_sigmask_is_macro = yes; then
> +              dnl On MinGW pthread_sigmask is just a macro which always 
> return 0.
> +              dnl It does not exist as a real function, which is required by 
> POSIX.
> +              REPLACE_PTHREAD_SIGMASK=1
> +              gl_cv_func_pthread_sigmask_in_LIBMULTITHREAD=no
> +            fi
> +          fi
> +          if test $gl_cv_func_pthread_sigmask_in_LIBMULTITHREAD = yes; then
>              dnl pthread_sigmask is available with -pthread or -lpthread.
>              LIB_PTHREAD_SIGMASK="$LIBMULTITHREAD"
>            else
> --
> Kind regards,
> Pavel Fedin
> Expert Engineer
> Samsung Electronics Research center Russia
> 
> 
> 
> 
> 

Pushed.

thanks,
Pádraig