Re: [PATCH] tests/unit/test-io-channel-command: Silence GCC error "maybe-uninitialized"

[Laurent Vivier]

Le 01/11/2022 à 22:39, Bernhard Beschow a écrit :
> GCC issues a false positive warning, resulting in build failure with -Werror:
>
>    In file included from /usr/lib/glib-2.0/include/glibconfig.h:9,
>                     from /usr/include/glib-2.0/glib/gtypes.h:34,
>                     from /usr/include/glib-2.0/glib/galloca.h:34,
>                     from /usr/include/glib-2.0/glib.h:32,
>                     from ../src/include/glib-compat.h:32,
>                     from ../src/include/qemu/osdep.h:144,
>                     from ../src/tests/unit/test-io-channel-command.c:21:
>    /usr/include/glib-2.0/glib/gmacros.h: In function 
> ‘test_io_channel_command_fifo’:
>    /usr/include/glib-2.0/glib/gmacros.h:1333:105: error: ‘dstargv’ may be used 
> uninitialized [-Werror=maybe-uninitialized]
>     1333 |   static G_GNUC_UNUSED inline void _GLIB_AUTO_FUNC_NAME(TypeName) 
> (TypeName *_ptr) { if (*_ptr != none) (func) (*_ptr); }     \
>          |                                                                      
>                                    ^
>    ../src/tests/unit/test-io-channel-command.c:39:19: note: ‘dstargv’ was 
> declared here
>       39 |     g_auto(GStrv) dstargv;
>          |                   ^~~~~~~
>    /usr/include/glib-2.0/glib/gmacros.h:1333:105: error: ‘srcargv’ may be used 
> uninitialized [-Werror=maybe-uninitialized]
>     1333 |   static G_GNUC_UNUSED inline void _GLIB_AUTO_FUNC_NAME(TypeName) 
> (TypeName *_ptr) { if (*_ptr != none) (func) (*_ptr); }     \
>          |                                                                      
>                                    ^
>    ../src/tests/unit/test-io-channel-command.c:38:19: note: ‘srcargv’ was 
> declared here
>       38 |     g_auto(GStrv) srcargv;
>          |                   ^~~~~~~
>    cc1: all warnings being treated as errors
>
> GCC version:
>
>    $ gcc --version
>    gcc (GCC) 12.2.0
>
> Fixes: 68406d10859385c88da73d0106254a7f47e6652e ('tests/unit: cleanups for 
> test-io-channel-command')
> Signed-off-by: Bernhard Beschow <shentey@gmail.com>
> ---
>   tests/unit/test-io-channel-command.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/tests/unit/test-io-channel-command.c 
> b/tests/unit/test-io-channel-command.c
> index 43e29c8cfb..ba0717d3c3 100644
> --- a/tests/unit/test-io-channel-command.c
> +++ b/tests/unit/test-io-channel-command.c
> @@ -35,8 +35,8 @@ static void test_io_channel_command_fifo(bool async)
>       g_autofree gchar *fifo = g_strdup_printf("%s/%s", tmpdir, TEST_FIFO);
>       g_autoptr(GString) srcargs = g_string_new(socat);
>       g_autoptr(GString) dstargs = g_string_new(socat);
> -    g_auto(GStrv) srcargv;
> -    g_auto(GStrv) dstargv;
> +    g_auto(GStrv) srcargv = NULL;
> +    g_auto(GStrv) dstargv = NULL;
>       QIOChannel *src, *dst;
>       QIOChannelTest *test;
>   

Applied to my trivial-patches branch.

Thanks,
Laurent