Here are some pre-built TensorFlow binaries you can use for each platform:
https://www.tensorflow.org/install/source_windows
pacman -S git patch unzip
bazel build --config=opt //tensorflow:libtensorflow.so
bazel build --config=opt //tensorflow/tools/pip_package:build_pip_package
bazel-bin\tensorflow\tools\pip_package\build_pip_package C:/tmp/tensorflow_pkg
pip install C:/tmp/tensorflow_pkg/tensorflow-1.13.0-cp36-cp36m-win_amd64.whl