pcl/fix with_openmp and with_opencv options not being applied

[trns1997]

Summary

Changes to recipe: recipes/pcl/1.14.x

Closes #28985

Motivation

The with_openmp and with_opencv options for the pcl package are not being applied when set via conanfile.txt. Even when explicitly enabling these options, the resulting PCL build behaves as if they are disabled.

Details

Options such as:

pcl/*:with_openmp=True

are ignored during configuration. CMake output confirms that OpenMP and OpenCV support are not enabled, and PCL prints warnings during configuration indicating that OpenMP is disabled.

This change aims to ensure that the option values passed from profiles or conanfile.txt are properly forwarded to the build system and not overwritten in recipe logic (e.g. config_options, configure, or CMake toolchain integration).

Additionally, I discovered that although with_opencv defaults to True in the recipe, OpenCV is never actually enabled nor installed because the current CMake option propagation and dependency checks prevent the condition from ever being met. So even when explicitly enabling with_opencv, the build proceeds without OpenCV support, making the default value misleading and ineffective. Maybe we should consider simplifying this mechanism to prevent confusion?

---

• Read the contributing guidelines
• Checked that this PR is not a duplicate: list of PRs by recipe
• If this is a bug fix, please link related issue or provide bug details
• Tested locally with at least one configuration using a recent version of Conan

---

Add a 👍 reaction to pull requests you find important to help the team prioritize, thanks!

[jcar87]

CMake output confirms that OpenMP and OpenCV support are not enabled, and PCL prints warnings during configuration indicating that OpenMP is disabled.

thanks @trns1997 - could you provide logs both before and after the proposed changes so that we can verify this? thanks!

[trns1997]

CMake output confirms that OpenMP and OpenCV support are not enabled, and PCL prints warnings during configuration indicating that OpenMP is disabled.

thanks @trns1997 - could you provide logs both before and after the proposed changes so that we can verify this? thanks!

Sorry it took me a while. Here are the logs you requested.
To verify that OpenMP is correctly enabled/disabled, I created a dedicated test_package_omp that uses:

pcl::NormalEstimationOMP<pcl::PointXYZ, pcl::Normal>

This class prints a warning when OpenMP is not available, and prints nothing when OpenMP is enabled.
Below are the results before/after applying the proposed fix.

Case 1: with_openmp=False

Command:

clear && conan create . -o pcl/*:with_openmp=False --build=missing --version 1.14.1 -tf test_package_omp

Output:

pcl/1.14.1 (test package): Running CMake.build()
pcl/1.14.1 (test package): RUN: cmake --build "/home/thomas/conan-center-index/recipes/pcl/all/test_package_omp/build/gcc-11-x86_64-gnu17-release" -- -j8
[ 50%] Building CXX object CMakeFiles/test_package.dir/test_package.cpp.o
[100%] Linking CXX executable test_package
[100%] Built target test_package

======== Testing the package: Executing test ========
pcl/1.14.1 (test package): Running test()
pcl/1.14.1 (test package): RUN: ./test_package
[pcl::NormalEstimationOMP::setNumberOfThreads] Parallelization is requested, but OpenMP is not available! Continuing without parallelization.
[pcl::NormalEstimationOMP::setNumberOfThreads] Parallelization is requested, but OpenMP is not available! Continuing without parallelization.
Requested threads = 4
Computed normals: 1000

As expected, PCL warns that OpenMP is not available.

Case 2: with_openmp=True

Command:

clear && conan create . -o pcl/*:with_openmp=True --build=missing --version 1.14.1 -tf test_package_omp

Output:

pcl/1.14.1 (test package): Running CMake.build()
pcl/1.14.1 (test package): RUN: cmake --build "/home/thomas/conan-center-index/recipes/pcl/all/test_package_omp/build/gcc-11-x86_64-gnu17-release" -- -j8
[ 50%] Building CXX object CMakeFiles/test_package.dir/test_package.cpp.o
[100%] Linking CXX executable test_package
[100%] Built target test_package

======== Testing the package: Executing test ========
pcl/1.14.1 (test package): Running test()
pcl/1.14.1 (test package): RUN: ./test_package
Requested threads = 4
Computed normals: 1000

No warnings are printed, confirming that OpenMP is correctly enabled.

I have left the test_package_omp sources here for referencing purposes. But I will remove it once you give the green light.

[trns1997]

remove before merge

[trns1997]

remove before merge

[trns1997]

remove before merge