CI: "Zephyr build from lastest on mail " fails

[arnopo]

Since the merge of zephyrproject-rtos/zephyr@4c1275d the CI is failed.

CMake Error at zephyrproject/zephyr/cmake/modules/version.cmake:66 (string):
  Syntax error in cmake code at

    /github/workspace/zephyrproject/zephyr/cmake/modules/version.cmake:66

  when parsing string

    EXTRAVERSION = ([a-z0-9\.\-]*)

  Invalid escape sequence \.
Call Stack (most recent call first):
  zephyrproject/zephyr/share/zephyr-package/cmake/ZephyrConfigVersion.cmake:59 (include)
  cmake/syscheck.cmake:8 (find_package)
  CMakeLists.txt:17 (include)

The issue seems linked to the syntax in the cmake/modules/version.cmake file

A fix has been proposed in zephyr:
zephyrproject-rtos/zephyr#85724

[arnopo]

Analysis from @tejlmand in zephyrproject-rtos/zephyr#85724 (review)
shows that the issue in In OpenAMP that not well manage cmake policy

I can see two options:

1- Increase the minimum version of CMake in libmetal's CMakeLists.txt.

• The current minimum CMake version is 3.0.2 (Dec 3, 2018).
• Zephyr requests a minimum CMake version of 3.20 (Apr 8, 2021).
• This could be an opportunity to remove the management of old policies CMP0048 and CMP0077.

2- Activate the CMP0053 policy in libmetal's CMakeLists.txt.

• This policy was introduced in CMake 3.1.

Cmake
if (POLICY CMP0053)
  cmake_policy(SET CMP0053 NEW)
endif()

I would be in favor of migrating to CMake 3.20.

@tnmysh @edmooring @wmamills and other do you see an issue for migrating to cmake 3.20?

[wmamills]

@arnopo Ubuntu 20.04 which is still supported has cmake 3.16.3
of course you can install a newer one with pip or from the kitware archive and you would need to for zephyr.
However if not using Zephyr it would be nice to be compatible with the one from 20.04

Can we use 3.16 as a minimum?

(debian bullseye aka oldstable has 3.18.4)

[wmamills]

Actually Ubuntu 20.04 is public EOL in April of this year. It is still supported for pro customers until April 2030.
Ubuntu 22.04 has cmake version 3.22.1 so 3.20 would be OK.

I am ok with either 3.16 or 3.20 as min version

[arnopo]

Actually Ubuntu 20.04 is public EOL in April of this year. It is still supported for pro customers until April 2030. Ubuntu 22.04 has cmake version 3.22.1 so 3.20 would be OK.

I am ok with either 3.16 or 3.20 as min version

Version 3.16 is OK. Regarding CMake policies, we are compatible with CMake 3.13 and higher.

[arnopo]

I pushed a PR #327 that update to 3.16 , I also tested for open-amp and I will push it later if everyone is OK to go in this direction

[wmamills]

@arnopo why did my open-amp PR#636 pass all tests including the latest zephyr test??
OpenAMP/open-amp#636

[arnopo]

@arnopo why did my open-amp PR#636 pass all tests including the latest zephyr test?? OpenAMP/open-amp#636

In libmetal, we use the cmake command to build libmetal for different architectures. In OpenAMP CI, we are using the west command. The Zephyr build chain seems to handle the check of the VERSION file present in libmetal and open-amp differently depending on the command used.