Ok i installed the 32bit libraries
$ sudo apt-get install libc6-dev-i386
but now the ld is confused
==== Building nspr ====
Linking nspr
/usr/bin/ld: i386:x86-64 architecture of input file `obj/Debug/
prgcleak.o' is incompatible with i386 output
/usr/bin/ld: i386:x86-64 architecture of input file `obj/Debug/
os_Linux_x86.o' is incompatible with i386 output