[Qemu-devel] [PULL 3/3] test qgraph.c: Fix segs due to out of scope default

[Thomas Huth <thuth@redhat.com>]

From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>

The test uses the trick:
   if (!opts) {
     opts = &(QOSGraph...Options) { };
   }

  in a couple of places, however the temporary created
by the &() {}  goes out of scope at the bottom of the if,
and results in a seg or assert when opts-> fields are
used (on fedora 30's gcc 9).

Fixes: fc281c802022cb3a73a5
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20190405184037.16799-1-dgilbert@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 tests/libqos/qgraph.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tests/libqos/qgraph.c b/tests/libqos/qgraph.c
index 122efc1b7b..b149caaaa9 100644
--- a/tests/libqos/qgraph.c
+++ b/tests/libqos/qgraph.c
@@ -77,6 +77,7 @@ static void add_edge(const char *source, const char *dest,
 {
     char *key;
     QOSGraphEdgeList *list = g_hash_table_lookup(edge_table, source);
+    QOSGraphEdgeOptions def_opts = { };
 
     if (!list) {
         list = g_new0(QOSGraphEdgeList, 1);
@@ -85,7 +86,7 @@ static void add_edge(const char *source, const char *dest,
     }
 
     if (!opts) {
-        opts = &(QOSGraphEdgeOptions) { };
+        opts = &def_opts;
     }
 
     QOSGraphEdge *edge = g_new0(QOSGraphEdge, 1);
@@ -590,9 +591,10 @@ void qos_add_test(const char *name, const char *interface,
 {
     QOSGraphNode *node;
     char *test_name = g_strdup_printf("%s-tests/%s", interface, name);;
+    QOSGraphTestOptions def_opts = { };
 
     if (!opts) {
-        opts = &(QOSGraphTestOptions) { };
+        opts = &def_opts;
     }
     node = create_node(test_name, QNODE_TEST);
     node->u.test.function = test_func;
-- 
2.21.0