Re: avoid two GCC11 warnings

[Jim Meyering]

On Thu, Nov 26, 2020 at 6:11 AM Bruno Haible <bruno@clisp.org> wrote:
> > Building grep with GCC11, I noticed some new warnings.
> > Fixed with the just-pushed attached patches.
>
> Thanks. It's interesting to see GCC's inference capabilities to grow.
>
> But the second patch causes a compilation error on MSVC:
>
> test-raise.c(20): fatal error C1083: Cannot open include file: 'unistd.h': No 
> such file or directory
> make[4]: *** [Makefile:718: test-raise.obj] Error 2
>
> This could be fixed in two ways:
>
> a) Change
>
> #include <unistd.h>
>
> to
>
> /* Get _exit.  */
> #if defined _WIN32 && !defined __CYGWIN__
> # include <stdlib.h>
> #else
> # include <unistd.h>
> #endif
>
> b) Adding a module dependency to 'unistd', since that guarantees that '_exit'
> is declared in <unistd.h> (see
> <https://www.gnu.org/software/gnulib/manual/html_node/unistd_002eh.html>).
>
> The latter is obviously preferred.
>
>
> 2020-11-26  Bruno Haible  <bruno@clisp.org>
>
>         raise-tests: Fix compilation error on MSVC (regression 2020-11-25).
>         * modules/raise-tests (Depends-on): Add unistd.
>         * doc/posix-functions/_exit.texi: Mention the 'unistd' module.

Hi Bruno,

Thanks for adding that. I did wonder, and even looked at
doc/posix-functions/_exit.texi. Quite a few modules of _exit-using
code will have to add that new dependency.

You've probably already started working on this, but I had to check...

Here's a first crack at the list of modules with a use of _exit, yet
no dependency on unistd:

$ grep -L '^unistd$' $(git grep -wlf<(git grep -wl _exit|grep -vE
'^(ChangeLog|doc)') modules)
modules/_Exit
modules/closein
modules/closeout
modules/forkpty
modules/grantpt
modules/memmem-simple
modules/nanosleep
modules/nanosleep-tests
modules/nocrash
modules/posix_spawn
modules/posix_spawn-internal
modules/posix_spawn_file_actions_addclose
modules/posix_spawn_file_actions_adddup2
modules/posix_spawn_file_actions_addopen
modules/posix_spawn_file_actions_destroy
modules/posix_spawn_file_actions_init
modules/posix_spawnattr_destroy
modules/posix_spawnattr_getflags
modules/posix_spawnattr_getpgroup
modules/posix_spawnattr_getschedparam
modules/posix_spawnattr_getschedpolicy
modules/posix_spawnattr_getsigdefault
modules/posix_spawnattr_getsigmask
modules/posix_spawnattr_init
modules/posix_spawnattr_setflags
modules/posix_spawnattr_setpgroup
modules/posix_spawnattr_setschedparam
modules/posix_spawnattr_setschedpolicy
modules/posix_spawnattr_setsigdefault
modules/posix_spawnattr_setsigmask
modules/posix_spawnp
modules/savewd
modules/sleep-tests
modules/stat-time-tests
modules/strcasestr-simple
modules/strstr-simple
modules/tmpfile-safer
modules/unistd