Fwd: [PATCH v5 01/18] ui: avoid compiler warnings from unused clipboard info variable

[Thomas Huth]

 Hi,

I think this might be a good candiate for the 6.2.1 stable release later... 
(people already ran into this issue and reported it in the bug tracker, see 
https://gitlab.com/qemu-project/qemu/-/issues/831 ).

 Thomas

-------- Forwarded Message --------
Subject: [PATCH v5 01/18] ui: avoid compiler warnings from unused clipboard 
info variable
Date: Wed, 15 Dec 2021 14:19:32 +0000
From: Daniel P. Berrangé <berrange@redhat.com>
To: qemu-devel@nongnu.org
CC: Thomas Huth <thuth@redhat.com>, Fam Zheng <fam@euphon.net>, Willian 
Rampazzo <willianr@redhat.com>, Peter Maydell <peter.maydell@linaro.org>, 
Beraldo Leal <bleal@redhat.com>, Gerd Hoffmann <kraxel@redhat.com>, Philippe 
Mathieu-Daudé <philmd@redhat.com>, Alex Bennée <alex.bennee@linaro.org>, 
Philippe Mathieu-Daudé <f4bug@amsat.org>, Wainer dos Santos Moschetta 
<wainersm@redhat.com>, Daniel P. Berrangé <berrange@redhat.com>, Richard 
Henderson <richard.henderson@linaro.org>

With latest clang 13.0.0 we get

../ui/clipboard.c:47:34: error: variable 'old' set but not used 
[-Werror,-Wunused-but-set-variable]
    g_autoptr(QemuClipboardInfo) old = NULL;
                                 ^

The compiler can't tell that we only declared this variable in
order to get the side effect of free'ing it when out of scope.

This pattern is a little dubious for a use of g_autoptr, so
rewrite the code to avoid it.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
 ui/clipboard.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/ui/clipboard.c b/ui/clipboard.c
index d7b008d62a..7672058e84 100644
--- a/ui/clipboard.c
+++ b/ui/clipboard.c
@@ -44,12 +44,11 @@ void qemu_clipboard_peer_release(QemuClipboardPeer *peer,
  void qemu_clipboard_update(QemuClipboardInfo *info)
 {
-    g_autoptr(QemuClipboardInfo) old = NULL;
     assert(info->selection < QEMU_CLIPBOARD_SELECTION__COUNT);
      notifier_list_notify(&clipboard_notifiers, info);
 -    old = cbinfo[info->selection];
+    qemu_clipboard_info_unref(cbinfo[info->selection]);
     cbinfo[info->selection] = qemu_clipboard_info_ref(info);
 }
 -- 2.33.1