146db9f919
If the .data field of a QAPI Union is NULL, we don't need to free any of the union fields. Make use of the new visit_start_union interface to access this information and instruct the generated code to not visit these fields when this occurs. Cc: qemu-stable@nongnu.org Reported-by: Fam Zheng <famz@redhat.com> Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com> Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>