Setup and installation

The SpinalSim with Verilator as backend is supported on both Linux and Windows platforms.


Don’t forget to add the following in your build.sbt file

fork := true

And you will always need the following imports in your Scala testbench :

import spinal.core._
import spinal.core.sim._


You will also need a recent version of Verilator installed :

sudo apt-get install git make autoconf g++ flex bison -y  # First time prerequisites
git clone   # Only first time
unsetenv VERILATOR_ROOT  # For csh; ignore error if on bash
unset VERILATOR_ROOT  # For bash
cd verilator
git pull        # Make sure we're up-to-date
git checkout verilator_3_916
autoconf        # Create ./configure script
make -j$(nproc)
sudo make install
echo "DONE"


In order to get SpinalSim + Verilator working on windows, you have to do the following :

  • Install MSYS2

  • Via MSYS2 get gcc/g++/verilator (for verilator you can compile it from the sources)

  • Add bin and usrbin of MSYS2 into your windows PATH (ie : C:msys64usrbin;C:msys64mingw64bin)

Then you should be able to run SpinalSim + verilator from your Scala project without having to use MSYS2 anymore.

From a fresh install of MSYS2 MinGW 64-bits, you will have to run the following commands inside the MSYS2 MinGW 64-bits shell (enter commands one by one):

pacman -Syuu
#Close the MSYS2 shell once you're asked to
pacman -Syuu
pacman -S --needed base-devel mingw-w64-x86_64-toolchain \
                   git flex\

git clone
cd verilator
git pull
git checkout verilator_3_916
export PATH=/usr/bin/core_perl:$PATH
cp /usr/include/FlexLexer.h ./src

make -j$(nproc)
make install
echo "DONE"
#Add C:\msys64\usr\bin;C:\msys64\mingw64\bin to you windows PATH


Be sure that your PATH environnement variable is pointing to the JDK 1.8 and don’t contain a JRE installation.


Adding the MSYS2 bin folders into your windows PATH could potentialy have some side effects. It’s why it is safer to add them as last elements of the PATH to reduce their priority.