For using Abseil with the Bazel buildsystem, use the bazel branch.
Checkout the bazel branch and follow the readme there.
$ git clone --branch bazel https://github.com/abseil/abseil-hello abseil-hello
$ cd abseil-hello
or if you already cloned this branch, switch to the bazel branch
$ git checkout bazel
For using Abseil with the CMake meta-buildsystem, use the cmake branch.
Checkout the cmake branch and follow the readme there.
$ git clone --branch cmake https://github.com/abseil/abseil-hello abseil-hello
$ cd abseil-hello
$ git submodule update --init
or if you already cloned this branch, switch to the cmake branch
$ git checkout cmake
$ git submodule update --init