Test C++11 code on GHA with C++98 config.

[s-trinh]

There seems to be an issue with C++98 builds when ur_rtde is built:

    - name: Install ur_rtde dependency
      run: |
        sudo add-apt-repository -y ppa:sdurobotics/ur-rtde
        sudo apt-get update
        sudo apt install -y librtde librtde-dev libboost-system-dev libboost-thread-dev libboost-program-options-dev

• first commit:
  • there are C++11 code both in the ViSP library and in ‎apps/calibration/intrinsic/visp-calibrate-camera.cpp
  • the ViSP library builds fine
  • running visp-calibrate-camera gives:

  Compiler with C++11 support is required.
  ptr=5
  C++11 code in vpMath::isInf())
  ptr=50

  • meaning VISP_CXX_STANDARD is correctly set (VISP_CXX_STANDARD < VISP_CXX_STANDARD_11)
  • but ViSP is actually built with C++11 flag

cf the raw log where -std=c++11 flag is passed:

2026-03-13T12:12:15.9307144Z [ 81%] Building CXX object modules/robot/CMakeFiles/visp_robot.dir/src/wireframe-simulator/vpVwstack.cpp.o
2026-03-13T12:12:15.9320323Z cd /home/runner/work/visp/visp/build/modules/robot && /usr/bin/g++ -Dvisp_EXPORTS -I/home/runner/work/visp/visp/build/include -I/home/runner/work/visp/visp/modules/robot/include -I/home/runner/work/visp/visp/modules/robot/src -I/home/runner/work/visp/visp/build/modules/robot -I/home/runner/work/visp/visp/modules/core/include -I/home/runner/work/visp/visp/modules/gui/include -I/home/runner/work/visp/visp/modules/io/include -I/home/runner/work/visp/visp/modules/sensor/include -isystem /usr/include/eigen3 -isystem /usr/include/libusb-1.0 -Wall -Wextra -Wno-c++11-compat -Wno-c++0x-compat -fopenmp -fvisibility=hidden -fvisibility-inlines-hidden -msse2 -msse3 -mssse3 -fPIC -O3 -DNDEBUG -std=c++11 -fPIC -MD -MT modules/robot/CMakeFiles/visp_robot.dir/src/wireframe-simulator/vpVwstack.cpp.o -MF CMakeFiles/visp_robot.dir/src/wireframe-simulator/vpVwstack.cpp.o.d -o CMakeFiles/visp_robot.dir/src/wireframe-simulator/vpVwstack.cpp.o -c /home/runner/work/visp/visp/modules/robot/src/wireframe-simulator/vpVwstack.cpp

• second commit:
  • removal of ur_rtde
  • ViSP build correctly failed

[fspindle]

@s-trinh The following error with Apriltag (link to GHA) line 1957

cd /home/runner/work/visp/visp/build/modules/detection && /usr/bin/g++ -Dvisp_EXPORTS -I/home/runner/work/visp/visp/build/include -I/home/runner/work/visp/visp/modules/detection/include -I/home/runner/work/visp/visp/modules/detection/src -I/home/runner/work/visp/visp/build/modules/detection -I/home/runner/work/visp/visp/modules/core/include -I/home/runner/work/visp/visp/modules/io/include -I/home/runner/work/visp/visp/modules/tracker/me/include -I/home/runner/work/visp/visp/modules/tracker/blob/include -I/home/runner/work/visp/visp/modules/visual_features/include -I/home/runner/work/visp/visp/modules/vision/include -isystem /usr/include/eigen3 -isystem /usr/include/apriltag -Wall -Wextra -Wno-c++11-compat -Wno-c++0x-compat -fopenmp -fvisibility=hidden -fvisibility-inlines-hidden -msse2 -msse3 -mssse3 -fPIC -O3 -DNDEBUG -std=c++98 -fPIC -MD -MT modules/detection/CMakeFiles/visp_detection.dir/src/tag/vpDetectorAprilTag.cpp.o -MF CMakeFiles/visp_detection.dir/src/tag/vpDetectorAprilTag.cpp.o.d -o CMakeFiles/visp_detection.dir/src/tag/vpDetectorAprilTag.cpp.o -c /home/runner/work/visp/visp/modules/detection/src/tag/vpDetectorAprilTag.cpp
/home/runner/work/visp/visp/modules/detection/src/tag/vpDetectorAprilTag.cpp: In static member function ‘static vpDetectorAprilTag::vpAprilTagFamily vpDetectorAprilTag::tagFamilyFromString(const std::string&)’:
/home/runner/work/visp/visp/modules/detection/src/tag/vpDetectorAprilTag.cpp:1531:66: error: ‘vpDetectorAprilTag::vpAprilTagFamily’ is not a class or namespace
 1531 |   vpDetectorAprilTag::vpAprilTagFamily res = vpDetectorAprilTag::vpAprilTagFamily::TAG_COUNT;
      |                                                                  ^~~~~~~~~~~~~~~~                                                               ^~~~~~~~~~~~~~~~

is fixed in PR #1927, with commit 572d511

Having this error means for me that the build is in cxx98 and not cxx11. This is confirmed with the option -std=c++98 that is used.

[s-trinh]

Commit 2 and 3 here are without ur_rtde. That's why the build successfully failed.

The C++98 builds should have failed long time ago.

---

Commit 1: everything passed but should not. I even put C++11 code directly in vpMath to make it fail. But the build still succeeded.

The log: https://github.com/lagadic/visp/actions/runs/23050111741/job/66948887696

Gives plenty of std=c++11 flag:

[fspindle]

@s-trinh I agree that there is something weird.

With visp-3.6.0 when -DUSE_CXX_STANDARD=98 -DUSE_EIGEN3=OFF -DUSE_PCL=OFF -DUSE_OPENCV=OFF the -std=c++11 flag is not used.

Some changes were introduced...

[fspindle]

@s-trinh Should be fixed in PR #1927, see issue #1929

[s-trinh]

@fspindle
Thanks, the issue is solved 👍