Compiling 32 bit binaries/libraries on 64 Bit OS - Ubuntu 12.04

On 64 bit 0S 32 bit compile and run time include and libraries are not present by default
we need to install these dependencies
below are few of packages that are required

sudo apt-get install ia32-libs libc-i386 libc6-dev-i386

Without these dependencies
u will be unable to compile 32 bit libs/binaries

withput lib6-dev-i386 u may encounter the error
/usr/include/features.h:323:26: fatal error: bits/predefs.h: No such file or directory