Build emacs snapshot on ubuntu 12.04

Hi,

I am trying to build emacs snapshot (from GIT repository) on Ubuntu 12.04.

When I do 'make', it just hangs at the following line 'In
Org-babel-edit-distance' and cpu goes up to 100%

cd lisp && make all                          \
	  CC='gcc -std=gnu99' CFLAGS='-g -O2' CPPFLAGS='' \
	  LDFLAGS='-Wl,-znocombreloc ' MAKE='make'
make[1]: Entering directory `/home/cheungs/Src/emacs/lisp'
make[2]: Entering directory `/home/cheungs/Src/emacs/lisp'
Compiling org/ob.el

In org-babel-edit-distance:
org/ob.el:598:31:Warning: function `cl-coerce' from cl package called at
    runtime

Has anyone see the same issue and know how to fix it?

Thank you.