[lttng-dev] Compilation error while building ust 1.9.4

[Harsh Bora]

Hi,
While building LTTng ust 1.9.4 with urcu 0.6.6, I get following 
compilation errors:

   CC     lttng-probe-ust.lo
   CC     lttng-context-vtid.lo
   CC     lttng-context-vpid.lo
   CC     lttng-context-pthread-id.lo
   CC     lttng-context-procname.lo
In file included from ../include/lttng/ust-events.h:23,
                  from lttng-context-procname.c:12:
/usr/local/include/urcu/hlist.h: In function ‘CDS_INIT_HLIST_HEAD’:
/usr/local/include/urcu/hlist.h:33: error: ‘NULL’ undeclared (first use 
in this function)
/usr/local/include/urcu/hlist.h:33: error: (Each undeclared identifier 
is reported only once
/usr/local/include/urcu/hlist.h:33: error: for each function it appears in.)
make[2]: *** [lttng-context-procname.lo] Error 1
make[2]: Leaving directory `/home/harsh/git-trees/lttng-ust/liblttng-ust'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/home/harsh/git-trees/lttng-ust'
make: *** [all] Error 2
[harsh at harshbora lttng-ust]$

Help ?

- Harsh