[OpenMP] [OMPD] Build gdb-plugin code only when python3 development files are available.

[Vigneshbalu]

Summary

This is follow-up patch to the review https://reviews.llvm.org/D100185.

gdb-plugin code is a interface between gdb, libompd, gdb and libomp. and Python3 development files are required to build this utility.
This patch will disable the plugin code build when python3 dev files are not available.

[aaronpuchert]

openmp/libompd/CMakeLists.txt

11–17

Use Python3_FOUND (see docs).

openmp/libompd/gdb-plugin/CMakeLists.txt

15–16

This should no longer be necessary if the parent directory finds it.

[mgorny]

openmp/libompd/CMakeLists.txt

11–12

I think option() is better for booleans.

https://cmake.org/cmake/help/latest/command/option.html

[Vigneshbalu]

openmp/libompd/CMakeLists.txt

11–17

Python3_Development_FOUND might be more suitable But i wonder whether it will be true when one of the artifacts was absent in rare scenario. Example Python3_INCLUDE_DIR is present but not Python3_LIBRARY
I assumed this would be safest.

[mgorny]

openmp/libompd/CMakeLists.txt

11–17

Python3_FOUND is FALSE if *any* of the requested components are missing. It's easy enough to check by renaming /usr/include/python3.x .

[Vigneshbalu]

openmp/libompd/CMakeLists.txt

11–17

I can see Python3_FOUND is false if i rename /usr/include/python3.x. However same is not true if i rename /usr/lib/x86_64-linux-gnu/libpython3.x.so . Even Python3_Development_FOUND doesn't work for above case.

this if check if (Python3_INCLUDE_DIRS AND Python3_LIBRARIES) also works fine with configuration if i rename library and fails at runtime.

I couldn't see any other reference anywhere in llvm-repo.
Am i missing something here ?

[mgorny]

openmp/libompd/CMakeLists.txt

11–17

It returns FALSE for me w/ CMake 3.24.2.

[Vigneshbalu]

Apologies for delay. Updated the patch.

[aaronpuchert]

Perhaps wait for @mgorny before you submit. Just a minor suggestion from me how you could simplify this.

openmp/libompd/CMakeLists.txt

11–16

[mgorny]

openmp/libompd/CMakeLists.txt

11–16

I think it should be good to go once you implement this suggestion.

[Vigneshbalu]

resolved review comments.

openmp/libompd/CMakeLists.txt

 #
 #//===----------------------------------------------------------------------===//
 #//
 #// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 #// See https://llvm.org/LICENSE.txt for license information.
 #// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 #//
 #//===----------------------------------------------------------------------===//
 #
 
+find_package (Python3 COMPONENTS Interpreter Development)
+option(LIBOMP_OMPD_GDB_SUPPORT "Build gdb-plugin code that enables OMPD support in GDB." ${Python3_FOUND})
+
 if(LIBOMP_OMPD_SUPPORT)
     set(OMPD_INCLUDE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/src/)
     add_subdirectory(src)
-    if(NOT DISABLE_OMPD_GDB_PLUGIN)
+    if(LIBOMP_OMPD_GDB_SUPPORT)
         add_subdirectory(gdb-plugin)
     endif()
 endif()

openmp/libompd/gdb-plugin/CMakeLists.txt

 #
 #//===----------------------------------------------------------------------===//
 #//
 #// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 #// See https://llvm.org/LICENSE.txt for license information.
 #// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 #//
 #//===----------------------------------------------------------------------===//
 #
 
 set (CMAKE_MODULE_PATH
     "${CMAKE_SOURCE_DIR}/libompd/"
     ${CMAKE_MODULE_PATH}
 )
 
-find_package (Python3 COMPONENTS Interpreter Development)
-find_package (PythonLibs REQUIRED)
-
 include_directories (${OMPD_INCLUDE_PATH})
 include_directories (${LIBOMP_INCLUDE_DIR})
 add_custom_command(OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/python-module/ompd/__init__.py
                    DEPENDS ompdModule.c ompdAPITests.c ompd/frame_filter.py ompd/__init__.py ompd/ompd_address_space.py ompd/ompd_callbacks.py ompd/ompd_handles.py ompd/ompd.py
                    COMMAND ${CMAKE_COMMAND} -E copy_directory ${CMAKE_CURRENT_SOURCE_DIR}/ompd ${CMAKE_CURRENT_BINARY_DIR}/python-module/ompd/
                    WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR})
 
 add_custom_target(ompd_gdb_plugin ALL
                   DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/python-module/ompd/__init__.py