Re: [PATCH] tests/plugin: prevent uninitialized warning

[Thomas Huth <thuth@redhat.com>]

On 06/02/2020 10.32, kuhn.chenqun@huawei.com wrote:
> From: Chen Qun <kuhn.chenqun@huawei.com>
> 
> According to the glibc function requirements, we need initialise
>  the variable. Otherwise there will be compilation warnings:
> 
> glib-autocleanups.h:28:3: warning: ‘out’ may be
> used uninitialized in this function [-Wmaybe-uninitialized]
>    g_free (*pp);
>    ^~~~~~~~~~~~
> 
> Reported-by: Euler Robot <euler.robot@huawei.com>
> Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com>
> ---
>  tests/plugin/bb.c   | 2 +-
>  tests/plugin/insn.c | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/tests/plugin/bb.c b/tests/plugin/bb.c
> index f30bea08dc..8b9da23a04 100644
> --- a/tests/plugin/bb.c
> +++ b/tests/plugin/bb.c
> @@ -22,7 +22,7 @@ static bool do_inline;
>  
>  static void plugin_exit(qemu_plugin_id_t id, void *p)
>  {
> -    g_autofree gchar *out;
> +    g_autofree gchar *out = NULL;
>      out = g_strdup_printf("bb's: %" PRIu64", insns: %" PRIu64 "\n",
>                            bb_count, insn_count);
>      qemu_plugin_outs(out);
> diff --git a/tests/plugin/insn.c b/tests/plugin/insn.c
> index 0a8f5a0000..c83b1c0157 100644
> --- a/tests/plugin/insn.c
> +++ b/tests/plugin/insn.c
> @@ -44,7 +44,7 @@ static void vcpu_tb_trans(qemu_plugin_id_t id, struct qemu_plugin_tb *tb)
>  
>  static void plugin_exit(qemu_plugin_id_t id, void *p)
>  {
> -    g_autofree gchar *out;
> +    g_autofree gchar *out = NULL;
>      out = g_strdup_printf("insns: %" PRIu64 "\n", insn_count);
>      qemu_plugin_outs(out);
>  }

Just a matter of taste, but I think in these simple cases, it would be
nicer to put everything in one line, e.g.:

    g_autofree gchar *out = g_strdup_printf("insns: %" PRIu64 "\n",
                                            insn_count);

Anyway,
Reviewed-by: Thomas Huth <thuth@redhat.com>