Can't compile LLVM project on Linux Debian

When I try to compile my LLVM-based project on a Debian (Jessie), the linker gives error saying that "-lz" doesn't found the lib.
I checked if libz.a exists and it actually doesn't exist. Why does it miss?

https://lmddgtfy.net/?q=jessie%20libz.a

https://packages.debian.org/jessie/zlib1g-dev

sudo apt-get install zlib1g-dev

Ben