commit f204cf51035f51b979dec18ee526e418139fa874
Author: Ján Tomko <jtomko@redhat.com>
Date:   Mon Aug 13 13:39:39 2018 +0200

    Revert "build: require Jansson if QEMU driver is enabled"
    
    This reverts commit 01ce04375c3348fd683475e5aa5231149ef6a78a.
    
    Jansson cannot parse QEMU's quirky JSON.
    Revert back to yajl.
    
    https://bugzilla.redhat.com/show_bug.cgi?id=1614569
    
    Signed-off-by: Ján Tomko <jtomko@redhat.com>
    Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>

Index: libvirt-4.6.0/m4/virt-driver-qemu.m4
===================================================================
--- libvirt-4.6.0.orig/m4/virt-driver-qemu.m4
+++ libvirt-4.6.0/m4/virt-driver-qemu.m4
@@ -27,9 +27,6 @@ AC_DEFUN([LIBVIRT_DRIVER_ARG_QEMU], [
 
 AC_DEFUN([LIBVIRT_DRIVER_CHECK_QEMU], [
   AC_REQUIRE([LIBVIRT_CHECK_JANSSON])
-  if test "$with_qemu:$with_jansson" = "yes:no"; then
-    AC_MSG_ERROR([Jansson >= 2.5 is required to build QEMU driver])
-  fi
   if test "$with_qemu" = "check"; then
     with_qemu=$with_jansson
   fi