libc6-dev-i386 - Embedded GNU C Library: 32-bit development libraries for AMD64
Contains the symlinks and object files needed to compile and link programs which use the standard C library. This is the 32bit version of the library, meant for AMD64 systems.
Download libc6-dev-i386_2.15-0ubuntu10_amd64.deb for Ubuntu 12.04 LTS
from the Ubuntu Main repository.
# sudo apt-get update
# sudo apt-get install libc6-dev-i386