Optional Build Information

This page contains additional information about the VTR build system, and how to build VTR on other OS platforms or with non-standard build options. If you only need to the default features of VTR on a Debian/Ubuntu system, the previous Building VTR page should be sufficient and you can skip this page.


Most package and Python dependencies can be installed using the instructions on the previous Building VTR page. However, more detailed information is provided here.


VTR uses CMake as it’s build system.

CMake provides a portable cross-platform build systems with many useful features.

For unix-like systems we provide a wrapper Makefile which supports the traditional make and make clean commands, but calls CMake behind the scenes.

Tested Compilers

VTR requires a C++-14 compliant compiler. It is tested against the default compilers of all Debian and Ubuntu releases within their standard support lifetime. Currently, those are the following:

  • GCC/G++: 7, 8, 9, 10, 11

  • Clang/Clang++: 6, 7, 10

Other compilers may work but are untested (your milage may vary).

Package Dependencies

  • At minimum you will require:

    • A modern C++ compiler supporting C++14 (such as GCC >= 4.9 or clang >= 3.6)

    • cmake, make

    • bison, flex, pkg-config

  • Additional packages are required for the VPR GUI (Cairo, FreeType, libXft, libX11, fontconfig, libgtk-3-dev)

  • The scripts to run the entire VTR flow, as well as the regressions scripts, require Python3 and Python packages listed in the requirements.txt file.

  • Developers may also wish to install other packages (git, ctags, gdb, valgrind, clang-format-7)

  • To generate the documentation you will need Sphinx, Doxygen, and several Python packages. The Python packages can be installed with the following command:

    pip install -r doc/requirements.txt

Build Options

Build Type

You can specify the build type by passing the BUILD_TYPE parameter.

For instance to create a debug build (no optimization and debug symbols):

#In the VTR root
$ make BUILD_TYPE=debug
[100%] Built target vpr

Passing parameters to CMake

You can also pass parameters to CMake.

For instance to set the CMake configuration variable VTR_ENABLE_SANITIZE on:

#In the VTR root
[100%] Built target vpr

Both the BUILD_TYPE and CMAKE_PARAMS can be specified concurrently:

#In the VTR root
[100%] Built target vpr

Using CMake directly

You can also use cmake directly.

First create a build directory under the VTR root:

#In the VTR root
$ mkdir build
$ cd build

#Call cmake pointing to the directory containing the root CMakeLists.txt
$ cmake ..

$ make

Changing configuration on the command line

You can change the CMake configuration by passing command line parameters.

For instance to set the configuration to debug:

#In the build directory
$ cmake . -DCMAKE_BUILD_TYPE=debug

$ make

Changing configuration interactively with ccmake

You can also use ccmake to to modify the build configuration.

#From the build directory
$ ccmake . #Make some configuration change

$ make

Other platforms

CMake supports a variety of operating systems and can generate project files for a variety of build systems and IDEs. While VTR is developed primarily on Linux, it should be possible to build on different platforms (your milage may vary). See the CMake documentation for more details about using cmake and generating project files on other platforms and build systems (e.g. Eclipse, Microsoft Visual Studio).


Nix can be used to build VTR on other platforms, such as MacOS.

If you don’t have Nix, you can get it with:

$ curl -L https://nixos.org/nix/install | sh

These commands will set up dependencies for Linux and MacOS and build VTR:

#In the VTR root
$ nix-shell dev/nix/shell.nix
$ make

Microsoft Windows

NOTE: VTR support on Microsoft Windows is considered experimental


The Windows Subsystem for Linux (WSL), “lets developers run a GNU/Linux environment – including most command-line tools, utilities, and applications – directly on Windows, unmodified, without the overhead of a traditional virtual machine or dual-boot setup.”

This is the recommended way to run VTR on Windows systems.


Cygwin provides a POSIX (i.e. unix-like) environment for Microsoft Windows.

From within the cygwin terminal follow the Unix-like build instructions listed above.

Note that the generated executables will rely upon Cygwin (e.g. cygwin1.dll) for POSIX compatibility.

Cross-compiling from Linux to Microsoft Windows with MinGW-W64

It is possible to cross-compile from a Linux host system to generate Microsoft Windows executables using the MinGW-W64 compilers. These can usually be installed with your Linux distribution’s package manager (e.g. sudo apt-get install mingw-w64 on Debian/Ubuntu).

Unlike Cygwin, MinGW executables will depend upon the standard Microsoft Visual C++ run-time.

To build VTR using MinGW:

#In the VTR root
$ mkdir build_win64
$ cd build_win64

#Run cmake specifying the toolchain file to setup the cross-compilation environment
$ cmake .. -DCMAKE_TOOLCHAIN_FILE ../cmake/toolchains/mingw-linux-cross-compile-to-windows.cmake

#Building will produce Windows executables
$ make

Note that by default the MS Windows target system will need to dynamically link to the libgcc and libstdc++ DLLs. These are usually found under /usr/lib/gcc on the Linux host machine.

See the toolchain file for more details.

Microsoft Visual Studio

CMake can generate a Microsft Visual Studio project, enabling VTR to be built with the Microsoft Visual C++ (MSVC) compiler.

Installing additional tools

VTR depends on some external unix-style tools during it’s buid process; in particular the flex and bison parser generators.

One approach is to install these tools using MSYS2, which provides up-to-date versions of many unix tools for MS Windows.

To ensure CMake can find the flex and bison executables you must ensure that they are available on your system path. For instance, if MSYS2 was installed to C:\msys64 you would need to ensure that C:\msys64\usr\bin was included in the system PATH environment variable.

Generating the Visual Studio Project

CMake (e.g. the cmake-gui) can then be configured to generate the MSVC project.