West build fails due to the toolchains python3 failing to run and reporting a version mismatch

[dberliner]

I am attempting to compile the peripheral_uart example targeting nrf52840dk, I've done quite a bit of work with zephyr but never with the nRF Connect SDK. I've encountered this on two different systems -- Manjaro and Ubuntu 22.04. After following the steps at https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/gs_installing.html and get the following error

dan@dan-MS-7C02:~/nrfbuild/nrf/samples/bluetooth/peripheral_uart$ west build -b nrf52840dk_nrf52840
-- west build: generating a build system
Loading Zephyr default modules (Zephyr base).
-- Application: /home/dan/nrfbuild/nrf/samples/bluetooth/peripheral_uart
-- Using NCS Toolchain 2.0.0 for building. (/home/dan/ncs/toolchains/v2.0.0/cmake)
CMake Error at /usr/share/cmake-3.22/Modules/FindPackageHandleStandardArgs.cmake:230 (message):
  Could NOT find Python3 (missing: Interpreter) (Required is exact version
  "3.10")

      Reason given by package: 
          Interpreter: Cannot run the interpreter "/home/dan/ncs/toolchains/v2.0.0/usr/local/bin/python3"

Call Stack (most recent call first):
  /usr/share/cmake-3.22/Modules/FindPackageHandleStandardArgs.cmake:594 (_FPHSA_FAILURE_MESSAGE)
  /usr/share/cmake-3.22/Modules/FindPython/Support.cmake:3180 (find_package_handle_standard_args)
  /usr/share/cmake-3.22/Modules/FindPython3.cmake:490 (include)
  /home/dan/nrfbuild/zephyr/cmake/modules/python.cmake:46 (find_package)
  /home/dan/nrfbuild/zephyr/cmake/modules/zephyr_default.cmake:121 (include)
  /home/dan/nrfbuild/zephyr/share/zephyr-package/cmake/ZephyrConfig.cmake:51 (include)
  /home/dan/nrfbuild/zephyr/share/zephyr-package/cmake/ZephyrConfig.cmake:76 (include_boilerplate)
  CMakeLists.txt:12 (find_package)


-- Configuring incomplete, errors occurred!
FATAL ERROR: command exited with status 1: /usr/bin/cmake -DWEST_PYTHON=/usr/bin/python3 -B/home/dan/nrfbuild/nrf/samples/bluetooth/peripheral_uart/build -S/home/dan/nrfbuild/nrf/samples/bluetooth/peripheral_uart -GNinja -DBOARD=nrf52840dk_nrf52840

This looks like an issue linking against the SDKs dynamic libraries, but when I add them to the path it shows up as the wrong version (v3.8.2 vs 3.10)

dan@dan-MS-7C02:~/nrfbuild$ /home/dan/ncs/toolchains/v2.0.0/usr/local/bin/python3
/home/dan/ncs/toolchains/v2.0.0/usr/local/bin/python3: error while loading shared libraries: libpython3.8.so.1.0: cannot open shared object file: No such file or directory
dan@dan-MS-7C02:~/nrfbuild$ LD_LIBRARY_PATH="/home/dan/ncs/toolchains/v2.0.0/usr/local/lib/" /home/dan/ncs/toolchains/v2.0.0/usr/local/bin/python3
Python 3.8.2 (default, Jun  2 2022, 09:16:00) 
[GCC 9.4.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> 

dan@dan-MS-7C02:~/nrfbuild/nrf/samples/bluetooth/peripheral_uart$ LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/home/dan/ncs/toolchains/v2.0.0/usr/local/lib/ west build -b nrf52840dk_nrf52840
-- west build: generating a build system
Loading Zephyr default modules (Zephyr base (cached)).
-- Application: /home/dan/nrfbuild/nrf/samples/bluetooth/peripheral_uart
-- Using NCS Toolchain 2.0.0 for building. (/home/dan/ncs/toolchains/v2.0.0/cmake)
CMake Error at /usr/share/cmake-3.22/Modules/FindPackageHandleStandardArgs.cmake:230 (message):
  Could NOT find Python3: Found unsuitable version "3.8.2", but required is
  exact version "3.10" (found
  /home/dan/ncs/toolchains/v2.0.0/usr/local/bin/python3, found components:
  Interpreter)
Call Stack (most recent call first):
  /usr/share/cmake-3.22/Modules/FindPackageHandleStandardArgs.cmake:592 (_FPHSA_FAILURE_MESSAGE)
  /usr/share/cmake-3.22/Modules/FindPython/Support.cmake:3180 (find_package_handle_standard_args)
  /usr/share/cmake-3.22/Modules/FindPython3.cmake:490 (include)
  /home/dan/nrfbuild/zephyr/cmake/modules/python.cmake:46 (find_package)
  /home/dan/nrfbuild/zephyr/cmake/modules/zephyr_default.cmake:121 (include)
  /home/dan/nrfbuild/zephyr/share/zephyr-package/cmake/ZephyrConfig.cmake:51 (include)
  /home/dan/nrfbuild/zephyr/share/zephyr-package/cmake/ZephyrConfig.cmake:81 (include_boilerplate)
  CMakeLists.txt:12 (find_package)


-- Configuring incomplete, errors occurred!
FATAL ERROR: command exited with status 1: /usr/bin/cmake -DWEST_PYTHON=/usr/bin/python3 -B/home/dan/nrfbuild/nrf/samples/bluetooth/peripheral_uart/build -S/home/dan/nrfbuild/nrf/samples/bluetooth/peripheral_uart -GNinja -DBOARD=nrf52840dk_nrf52840

[Charlie]

Hi Dan,

I will spend some time setting up an Ubuntu 22.04 to verify your finding.

I also have a reminder for you, from NCS2.0.0, you can do Installing automatically with nRF Connect for Desktop on a Linux machine(Ubuntu20.04 is fully tested) in several minutes. It is a much easier NCS deployment solution for Linux developers.

Best regards,

Charlie

[dberliner]

I ended up removing the toolchain entirely and my system tools (on Manjaro) were able to build everything I needed. I used the GUI tool to install the nRF toolchain in the original question.

[Charlie]

Hi Dan,

Thanks for the update, good to hear you solve the problem.

nRF Connect for Desktop Toolchain Manager APP is not fully tested with other Linux systems except Ubuntu20.04. Try GUI installation with Ubuntu20.04 if possible.

Best regards,

Charlie