block/vhdx.c: Mark parent_vhdx_guid variable as unused

The parent_vhdx_guid variable is defined but never used, which provokes
complaints from newer versions of clang. Since the variable definition
is here acting as documentation of the image format, mark it with the
'unused' attribute to keep the compiler happy rather than simply
deleting it.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

diff --git a/block/vhdx.c b/block/vhdx.c
index 796b7bd88450b38c0a0903edfd629d8c4710542c..d9aa2c14edf60c11638572916e454f50ed1d09c7 100644 (file)
--- a/block/vhdx.c
+++ b/block/vhdx.c
@@ -99,7 +99,8 @@ static const MSGUID logical_sector_guid = { .data1 = 0x8141bf1d,
 /* Each parent type must have a valid GUID; this is for parent images
  * of type 'VHDX'.  If we were to allow e.g. a QCOW2 parent, we would
  * need to make up our own QCOW2 GUID type */
-static const MSGUID parent_vhdx_guid = { .data1 = 0xb04aefb7,
+static const MSGUID parent_vhdx_guid __attribute__((unused))
+                                     = { .data1 = 0xb04aefb7,
                                          .data2 = 0xd19e,
                                          .data3 = 0x4a81,
                                          .data4 = { 0xb7, 0x89, 0x25, 0xb8,