[onert] Suggestion to modify unnecessary code according to pybind11 update

[김재만]

Background

Recently, I discovered that a long-standing bug in pybind11 has been fixed. This fix eliminates the need to directly import Python development components (libs, headers) from various Linux environments.

Reference to the current implementation:

ONE/runtime/onert/api/python/CMakeLists.txt

Lines 5 to 26 in 30d45e8

 # CMakeLists.txt 
  
 # refer to https://github.com/Samsung/ONE/issues/11368 
  
 # Tell pybind11 where the target python installation is 
 # 
 # FindPythonLibs is deprecated since 3.12, and recommand to use FindPython. 
 # But on cross compile, FindPython is not working for target environment 
 # For workaround, use PythonLibs 
 find_package(PythonLibs REQUIRED) 
 set(PYTHON_MODULE_PREFIX "lib" CACHE INTERNAL "Cross python lib prefix") 
 set(PYTHON_MODULE_EXTENSION ".so" CACHE INTERNAL "Cross python lib extension") 
  
 # Disable pybind11 python search mechanism 
 set(PYTHONLIBS_FOUND TRUE CACHE INTERNAL "") 
  
 # Install pybind11 
 nnfw_find_package(Pybind11 REQUIRED) 
 if(NOT Pybind11_FOUND) 
   message(STATUS "Build onert/python: FAILED (Pybind11 is missing)") 
   return() 
 endif() 

Proposed Change

Given this fix, I suggest updating the code to the following:

# Install pybind11
nnfw_find_package(Pybind11 REQUIRED)
if(NOT Pybind11_FOUND)
  message(STATUS "Build onert/python: FAILED (Pybind11 is missing)")
  return()
endif()

Opinion

I would like to know your thoughts on this proposed change.

Reference

For more details on the bug fix, please see: pybind/pybind11#4805

[Hyeongseok Oh]

Thanks your suggestion. Then we need to use more latest pybind11 version, right? (not currently using v2.11.1)

[김재만]

I understand that ONE is currently using pybind v2.11.1.

ONE/infra/cmake/packages/Pybind11SourceConfig.cmake

Lines 10 to 11 in 0d7274f

 envoption(EXTERNAL_DOWNLOAD_SERVER "https://github.com") 
 envoption(PYBIND11_URL ${EXTERNAL_DOWNLOAD_SERVER}/pybind/pybind11/archive/v2.11.1.tar.gz) 

And the above application requires the use of pybind 2.12.0 releasing version.

Pybind11 Version 2.12.0 - bug fixes List

If it is okay to use the currently released version of pybind11 v2.12.0, I will test it.

Reference

https://github.com/pybind/pybind11/releases

[Hyeongseok Oh]

Based on release note, this feature works on cmake 3.18+.
Since we are using cmake 3.16.3 (ubuntu 20.04's default cmake version), we cannot use this feature.

[김재만]

oh, I didn't check the cmake version
Thanks for checking this

[Hyeongseok Oh]

@jaemaning Thank you for inform us about this. When we ready to upgrade cmake version, we can use this feature.