Windows support is in beta. Known issues are marked with label “Windows” on github issues.
We currently support only 64 bit Windows 7 or higher and we compile Bazel as a msys2 binary.
Before you can compile or run Bazel, you will need to set some environment variables:
export JAVA_HOME="$(ls -d C:/Program\ Files/Java/jdk* | sort | tail -n 1)" export BAZEL_SH=c:/msys64/usr/bin/bash.exe
If you have another tool that vendors msys2 (such as msysgit), then c:\msys64\usr\bin must appear in your PATH before entries for those tools.
Similarly, if you have bash on Ubuntu on Windows installed, you should make sure c:\msys64\usr\bin appears in PATH before c:\windows\system32, because otherwise Windows' bash.exe is used before msys2's.
To run Bazel (even pre-built binaries), you will need:
Java JDK 8 or later.
Python 2.7 or later.
Several msys2 packages. Use the pacman command to install them:
pacman -Syuu git curl zip unzip
See Install Bazel on Windows for installation instructions.
Bazel now supports building C++, Java and Python targets on Windows.
To build C++ targets, you will need:
Visual Studio
We are using MSVC as the native C++ toolchain, so please ensure you have Visual Studio installed with the Visual C++ > Common Tools for Visual C++ and Visual C++ > Microsoft Foundation Classes for C++ features. (which is NOT the default installation type of Visual Studio). You can set BAZEL_VS environment variable to tell Bazel where Visual Studio is, otherwise Bazel will try to find the latest version installed.
For example: export BAZEL_VS="C:/Program Files (x86)/Microsoft Visual Studio 14.0"
Python
Both Python 2 and Python 3 are supported. Currently, we use Python wrapper scripts to call the actual MSVC compiler, so please make sure Python is installed and its location is added into PATH. It's also a good idea to set BAZEL_PYTHON environment variable to tell Bazel where Python is.
For example: export BAZEL_PYTHON=C:/Python27/python.exe
Bazel will auto-configure the location of Visual Studio and Python at the first time you build any target. If you need to auto-configure again, just run bazel clean then build a target.
If everything is set up, you can build C++ target now!
bazel build examples/cpp:hello-world ./bazel-bin/examples/cpp/hello-world.exe bazel run examples/cpp:hello-world
However, with Bazel version prior to 0.5.0, MSVC toolchain is not default on Windows, you should use flag --cpu=x64_windows_msvc to enable it like this:
bazel build --cpu=x64_windows_msvc examples/cpp:hello-world
Building Java targets works well on Windows, no special configuration is needed. Just try:
bazel build examples/java-native/src/main/java/com/example/myproject:hello-world ./bazel-bin/examples/java-native/src/main/java/com/example/myproject/hello-world bazel run examples/java-native/src/main/java/com/example/myproject:hello-world
On Windows, we build a self-extracting zip file for executable Python targets, you can even use python ./bazel-bin/path/to/target to run it in native Windows command line (cmd.exe). See more details in this design doc.
bazel build examples/py_native:bin ./bazel-bin/examples/py_native/bin python ./bazel-bin/examples/py_native/bin # This works in both msys and cmd.exe bazel run examples/py_native:bin