Regarding nextpnr installation issue

[ghanesimit]

I have followed below link to download tool on ubuntu 16.04.
http://www.clifford.at/icestorm/

Where I am facing issue while installing nextpnr as below.

$ cmake -DARCH=ice40 -DCMAKE_INSTALL_PREFIX=/usr/local .
-- Boost version: 1.58.0
-- Found the following Boost libraries:
-- filesystem
-- thread
-- program_options
-- iostreams
-- system
-- chrono
-- date_time
-- atomic
-- regex
CMake Error at CMakeLists.txt:197 (find_package):
Could not find a package configuration file provided by "Eigen3" with any
of the following names:

Eigen3Config.cmake
eigen3-config.cmake

Add the installation prefix of "Eigen3" to CMAKE_PREFIX_PATH or set
"Eigen3_DIR" to a directory containing one of the above files. If "Eigen3"
provides a separate development package or SDK, be sure it has been
installed.

-- Configuring incomplete, errors occurred!
See also "/home/SLSCORP/simit.ghane.457/Desktop/USB_2019/RISC_V/nextpnr/CMakeFiles/CMakeOutput.log".
See also "/home/SLSCORP/simit.ghane.457/Desktop/USB_2019/RISC_V/nextpnr/CMakeFiles/CMakeError.log".

Please guide me.

[daveshah1]

Please use the nextpnr repository for nextpnr issues in the future.

In this case you need to install libeigen3-dev