[24603] Add opt-in strict bool normalization

[mirkomorati]

Description

In release builds, the compiler optimizes the if (bool_t) { write 1 } else { write 0 } pattern in all the bool serialization paths.

This PR introduces a STRICT_BOOL CMake option (off by default), the relative FASTCDR_STRICT_BOOL compiler definition and a new launder_bool() helper function that uses memcpy and a compiler barrier to force normalization of boolean values to 0/1.
A dedicated test file BoolStrictTest.cpp has also been included that tests the "truthy" cases.

Since this is an opt-in, we can backport the new feature to 2.3.x, which is the most used branch.
@Mergifyio backport 2.3.x

Fixes #315

Contributor Checklist

• Commit messages follow the project guidelines.
• The code follows the style guidelines of this project.
• Tests that thoroughly check the new feature have been added/Regression tests checking the bug and its fix have been added; the added tests pass locally
• Any new/modified methods have been properly documented using Doxygen.
• Changes are backport compatible: they do NOT break ABI nor change library core behavior.
• Changes are API compatible.
• New feature has been added to the versions.md file (if applicable).
• Applicable backports have been included in the description.

Reviewer Checklist

• The PR has a milestone assigned.
• The title and description correctly express the PR's purpose.
• Check contributor checklist is correct.
• Check CI results: changes do not issue any warning.
• Check CI results: CI pass and failing tests are unrelated with the changes.

[MiguelCompany]

Thank you so much for this well-crafted PR.

Please take the following suggestions into consideration.

[MiguelCompany]

Thanks for the great work @mirkomorati

Now, for the final touches:

• Rebase on top of master
• Add a single line * Add STRICT_BOOL CMake option to enforce canonical bool serialization to versions.md

It would also be nice if you could add a way of testing the new feature in the CI job. If you don't have experience with GitHub Actions, or you'd prefer we take care of it, we'll do.

[mirkomorati]

Thank you for the review!

As you guessed I have little to no experience directly with github actions, but I hope the idea is correct:

• Expand the fastcdr_test matrix jobs to test with both builds
• Upload both test results

The add_labels step I think should be called once, so I added a check there.

Would something like this work? Or were you thinking about exposing a variable input.test-strict-bool to control it as an opt-in from the other CI jobs?

diff --git a/.github/workflows/reusable-ci.yml b/.github/workflows/reusable-ci.yml
index e0ab3b5..5ae1c4d 100644
--- a/.github/workflows/reusable-ci.yml
+++ b/.github/workflows/reusable-ci.yml
@@ -68,10 +68,13 @@ jobs:
       matrix:
         cmake-build-type:
           - 'RelWithDebInfo'
+        strict-bool:
+          - false
+          - true
 
     steps:
     - name: Add ci-pending label if PR
-      if: ${{ github.event_name == 'pull_request' && inputs.add-label == true}}
+      if: ${{ github.event_name == 'pull_request' && inputs.add-label == true && matrix.strict-bool == false }}
       uses: eProsima/eProsima-CI/external/add_labels@v0
       with:
         labels: ci-pending
@@ -122,7 +125,7 @@ jobs:
         colcon_meta_file: ${{ github.workspace }}/src/fastcdr/.github/workflows/config/build.meta
         colcon_build_args: ${{ inputs.colcon-args }}
         colcon_build_args_default: --event-handlers=console_direct+
-        cmake_args: ${{ inputs.cmake-args }}
+        cmake_args: ${{ inputs.cmake-args }} ${{ matrix.strict-bool == true && '-DSTRICT_BOOL=ON' || '' }}
         cmake_args_default: ${{ env.colcon-build-default-cmake-args }} ${{ env.toolset }}
         cmake_build_type: ${{ matrix.cmake-build-type }}
         workspace: ${{ github.workspace }}
@@ -137,7 +140,7 @@ jobs:
         ctest_args: ${{ inputs.ctest-args }}
         packages_names: fastcdr
         workspace: ${{ github.workspace }}
-        test_report_artifact: ${{ inputs.label }}
+        test_report_artifact: ${{ inputs.label }}${{ matrix.strict-bool == true && '-strict-bool' || '' }}
 
     - name: Fast CDR Test summary
       uses: eProsima/eProsima-CI/multiplatform/junit_summary@v0
@@ -153,5 +156,5 @@ jobs:
       if: always()
       uses: eProsima/eProsima-CI/external/upload-artifact@v0
       with:
-        name: test-results-${{ inputs.label }}
+        name: test-results-${{ inputs.label }}${{ matrix.strict-bool == true && '-strict-bool' || '' }}
         path: log/latest_test/fastcdr

[MiguelCompany]

@mirkomorati Looks like the thing I would do