Re: [PATCH] C++: "#define timeval rpl_timeval" -> typedef in GNULIB_NAMESPACE

[Bruno Haible]

Pedro Alves wrote in 
<https://lists.gnu.org/archive/html/bug-gnulib/2016-11/msg00058.html>:

> With GNULIB_NAMESPACE, we can do better: Make gnulib define
> GNULIB_NAMESPACE::timeval as a typedef to whatever "struct timeval" is
> (which is either the system's timeval or gnulib's rpl_timeval
> replacement), and #undef away the "#define timeval rpl_timeval".
> 
> With this, you now write:
> 
>   gnulib::timeval tv;
>   gnulib::gettimeofday (&tv, NULL);
> 
> Instead of:
> 
>   struct timeval tv;
>   gnulib::gettimeofday (&tv, NULL);
> 
> And now "struct timeval" refers to the system's timeval struct.  (That
> GDB wrapper for sys/time.h can then be removed, as having no effect.)

However, we (now? still?) have a compilation error on Mac OS X of the
signature tests of a C++ testdir:
$ ./gnulib-tool --create-testdir --dir=/tmp/testdir-posix --with-tests 
--with-c++-tests --single-configure `./posix-modules`

Namely:

In file included from test-fcntl-h-c++.cc:22:
In file included from ../gllib/fcntl.h:67:
In file included from ../gllib/unistd.h:40:
In file included from 
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.12.sdk/usr/include/unistd.h:638:
../gllib/sys/select.h:728:27: error: elaborated type refers to a typedef
                   struct timeval *restrict));
                          ^
../gllib/sys/time.h:568:5: note: declared here
    timeval;
    ^

In file included from test-stdlib-c++.cc:22:
In file included from ../gllib/stdlib.h:96:
In file included from ../gllib/unistd.h:40:
In file included from 
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.12.sdk/usr/include/unistd.h:638:
../gllib/sys/select.h:728:27: error: elaborated type refers to a typedef
                   struct timeval *restrict));
                          ^
../gllib/sys/time.h:568:5: note: declared here
    timeval;
    ^

In file included from test-sys_ioctl-c++.cc:22:
In file included from ../gllib/sys/ioctl.h:37:
In file included from ../gllib/unistd.h:40:
In file included from 
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.12.sdk/usr/include/unistd.h:638:
../gllib/sys/select.h:728:27: error: elaborated type refers to a typedef
                   struct timeval *restrict));
                          ^
../gllib/sys/time.h:568:5: note: declared here
    timeval;
    ^

In file included from test-sys_select-c++.cc:22:
../gllib/sys/select.h:728:27: error: elaborated type refers to a typedef
                   struct timeval *restrict));
                          ^
../gllib/sys/time.h:568:5: note: declared here
    timeval;
    ^

In file included from test-unistd-c++.cc:22:
In file included from ../gllib/unistd.h:40:
In file included from 
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.12.sdk/usr/include/unistd.h:638:
../gllib/sys/select.h:728:27: error: elaborated type refers to a typedef
                   struct timeval *restrict));
                          ^
../gllib/sys/time.h:568:5: note: declared here
    timeval;
    ^

Any ideas how to fix this?

Bruno