Build warnings: [-Wshadow]

[s-trinh]

It is more a bad practice than something severe:

• How bad is redefining/shadowing a local variable?

When doing:

• cmake ../visp -DBUILD_JAVA=OFF -DBUILD_MODULE_visp_java=OFF -DBUILD_MODULE_visp_java_binding=OFF -DCMAKE_CXX_FLAGS="-Wshadow -Wnon-virtual-dtor -Wpedantic"
• make -j8 2>&1 | tee build.log >(grep -i warning > warnings.txt)
• it gives plenty of warnings: warnings.txt

What is weird is that when doing -DACTIVATE_WARNING_SHADOW=ON instead of -DCMAKE_CXX_FLAGS=..., there are much less warnings:

• cmake ../visp -DACTIVATE_WARNING_SHADOW=ON -DBUILD_JAVA=OFF -DBUILD_MODULE_visp_java=OFF -DBUILD_MODULE_visp_java_binding=OFF -DCMAKE_CXX_FLAGS="-Wnon-virtual-dtor -Wpedantic"
• warnings in visp/3rdparty/simdlib/Simd are no more present
• maybe -DDACTIVATE_WARNING_SHADOW is not properly propagated to this lib?

visp/3rdparty/qbdevice/qbmove_communications.cpp:769:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_ACTIVATE’ to ‘-128’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:808:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_SET_BAUDRATE’ to ‘-112’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:846:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_SET_WATCHDOG’ to ‘-113’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:888:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_GET_ACTIVATE’ to ‘-127’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:889:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_GET_ACTIVATE’ to ‘-127’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:937:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_SET_INPUTS_ACK’ to ‘-109’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:983:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_SET_INPUTS’ to ‘-126’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:1026:20: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_SET_POS_STIFF’ to ‘-121’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:1070:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_GET_INPUTS’ to ‘-125’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:1071:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_GET_INPUTS’ to ‘-125’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:1205:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_GET_COUNTERS’ to ‘-118’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:1206:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_GET_COUNTERS’ to ‘-118’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:1296:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_GET_CURRENTS’ to ‘-123’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:1297:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_GET_CURRENTS’ to ‘-123’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:1349:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_GET_EMG’ to ‘-120’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:1350:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_GET_EMG’ to ‘-120’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:1404:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_GET_CURR_AND_MEAS’ to ‘-122’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:1405:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_GET_CURR_AND_MEAS’ to ‘-122’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:1468:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_GET_VELOCITIES’ to ‘-119’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:1469:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_GET_VELOCITIES’ to ‘-119’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:1550:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_GET_ACCEL’ to ‘-117’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:1551:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_GET_ACCEL’ to ‘-117’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:2213:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_EXT_DRIVE’ to ‘-111’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:2260:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_SET_CUFF_INPUTS’ to ‘-114’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:2300:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_GET_JOYSTICK’ to ‘-110’ [-Woverflow]
visp/3rdparty/qbdevice/qbmove_communications.cpp:2301:19: warning: overflow in conversion from ‘qbmove_command’ to ‘char’ changes value from ‘CMD_GET_JOYSTICK’ to ‘-110’ [-Woverflow]
visp/modules/core/src/image/vpFont.cpp:353:20: warning: declaration of ‘x’ shadows a previous local [-Wshadow]
visp/modules/core/src/image/vpFont.cpp:467:20: warning: declaration of ‘x’ shadows a previous local [-Wshadow]
visp/modules/tracker/dnn/src/vpMegaPose.cpp:572:10: warning: declaration of ‘j’ shadows a previous local [-Wshadow]
visp/modules/imgproc/src/vpCLAHE.cpp:163:12: warning: declaration of ‘i’ shadows a previous local [-Wshadow]
visp/modules/imgproc/src/vpCLAHE.cpp:173:12: warning: declaration of ‘i’ shadows a previous local [-Wshadow]
visp/modules/imgproc/src/vpCLAHE.cpp:196:12: warning: declaration of ‘i’ shadows a previous local [-Wshadow]
visp/modules/imgproc/src/vpCLAHE.cpp:201:12: warning: declaration of ‘i’ shadows a previous local [-Wshadow]
visp/modules/tracker/me/src/moving-edges/vpMeEllipse_least_square.cpp:219:14: warning: declaration of ‘x’ shadows a previous local [-Wshadow]
visp/modules/tracker/me/src/moving-edges/vpMeSite.cpp:54:32: warning: declaration of ‘site’ shadows a member of ‘vpMeSiteHypothesis’ [-Wshadow]
visp/modules/tracker/me/src/moving-edges/vpMeSite.cpp:54:32: warning: declaration of ‘site’ shadows a member of ‘vpMeSiteHypothesis’ [-Wshadow]
visp/modules/tracker/me/src/moving-edges/vpMeSite.cpp:54:32: warning: declaration of ‘site’ shadows a member of ‘vpMeSiteHypothesis’ [-Wshadow]
visp/modules/core/test/camera/catchJsonCamera.cpp:82:15: warning: declaration of ‘type’ shadows a member of ‘{anonymous}::vpRandomCamGenerator’ [-Wshadow]
visp/modules/core/test/image-with-dataset/catchColorConversion.cpp:980:7: warning: declaration of ‘height’ shadows a global declaration [-Wshadow]
visp/modules/core/test/image-with-dataset/catchColorConversion.cpp:980:43: warning: declaration of ‘width’ shadows a global declaration [-Wshadow]
visp/modules/core/test/image-with-dataset/catchColorConversion.cpp:1118:21: warning: declaration of ‘I_RGBA_8U’ shadows a previous local [-Wshadow]
visp/modules/core/test/image/testHSVGradient.cpp:116:52: warning: declaration of ‘const vpImage<bool>* p_mask’ shadows a parameter [-Wshadow]
visp/modules/core/test/image/testHSVGradient.cpp:199:52: warning: declaration of ‘const vpImage<bool>* p_mask’ shadows a parameter [-Wshadow]
visp/modules/core/test/image/testHSVGradient.cpp:116:52: warning: declaration of ‘const vpImage<bool>* p_mask’ shadows a parameter [-Wshadow]
visp/modules/core/test/image/testHSVGradient.cpp:199:52: warning: declaration of ‘const vpImage<bool>* p_mask’ shadows a parameter [-Wshadow]
visp/modules/core/test/image/testHSVGradient.cpp:116:52: warning: declaration of ‘const vpImage<bool>* p_mask’ shadows a parameter [-Wshadow]
visp/modules/core/test/image/testHSVGradient.cpp:199:52: warning: declaration of ‘const vpImage<bool>* p_mask’ shadows a parameter [-Wshadow]
visp/modules/core/test/image/testHSVGradient.cpp:116:52: warning: declaration of ‘const vpImage<bool>* p_mask’ shadows a parameter [-Wshadow]
visp/modules/core/test/image/testHSVGradient.cpp:199:52: warning: declaration of ‘const vpImage<bool>* p_mask’ shadows a parameter [-Wshadow]
visp/modules/core/test/math/catchJsonArrayConversion.cpp:233:21: warning: declaration of ‘j’ shadows a previous local [-Wshadow]
visp/modules/core/test/tools/io-with-dataset/testIoTools.cpp:827:9: warning: declaration of ‘nbFail’ shadows a previous local [-Wshadow]
visp/modules/core/test/tools/io-with-dataset/testIoTools.cpp:828:9: warning: declaration of ‘nbOk’ shadows a previous local [-Wshadow]
visp/modules/io/test/catchJsonArgumentParser.cpp:190:42: warning: declaration of ‘j’ shadows a previous local [-Wshadow]
visp/modules/io/test/catchJsonArgumentParser.cpp:205:42: warning: declaration of ‘j’ shadows a previous local [-Wshadow]
visp/modules/io/test/video/catchVideo.cpp:63:39: warning: declaration of ‘nframes’ shadows a global declaration [-Wshadow]
visp/modules/io/test/video/catchVideo.cpp:62:104: warning: declaration of ‘frame_step’ shadows a global declaration [-Wshadow]
visp/modules/io/test/video/catchVideo.cpp:62:87: warning: declaration of ‘first_frame’ shadows a global declaration [-Wshadow]
visp/modules/io/test/video/catchVideo.cpp:85:29: warning: declaration of ‘last_frame’ shadows a global declaration [-Wshadow]
visp/modules/io/test/video/catchVideo.cpp:84:94: warning: declaration of ‘frame_step’ shadows a global declaration [-Wshadow]
visp/modules/io/test/video/catchVideo.cpp:84:77: warning: declaration of ‘first_frame’ shadows a global declaration [-Wshadow]
visp/modules/io/test/video/catchVideo.cpp:174:15: warning: declaration of ‘tmp’ shadows a global declaration [-Wshadow]
visp/modules/visual_features/src/visual-feature/vpFeatureLuminanceMapping.cpp:555:67: warning: declaration of ‘I’ shadows a member of ‘vpFeatureLuminanceMapping’ [-Wshadow]
visp/modules/robot/src/real-robot/pololu-maestro/vpRobotPololuPtu.cpp:65:42: warning: declaration of ‘eJe’ shadows a member of ‘vpRobotPololuPtu’ [-Wshadow]
visp/modules/robot/src/real-robot/pololu-maestro/vpRobotPololuPtu.cpp:73:42: warning: declaration of ‘fJe’ shadows a member of ‘vpRobotPololuPtu’ [-Wshadow]
visp/modules/robot/src/real-robot/pololu-maestro/vpRobotPololuPtu.cpp:81:64: warning: declaration of ‘eJe’ shadows a member of ‘vpRobotPololuPtu’ [-Wshadow]
visp/modules/robot/src/real-robot/pololu-maestro/vpRobotPololuPtu.cpp:99:64: warning: declaration of ‘fJe’ shadows a member of ‘vpRobotPololuPtu’ [-Wshadow]
visp/modules/vision/src/key-point/vpKeyPoint.cpp:3369:78: warning: declaration of ‘detectionScore’ shadows a member of ‘vpKeyPoint’ [-Wshadow]
visp/modules/vision/src/plane-estimation/vpPlaneEstimation.cpp:77:90: warning: declaration of ‘const vpColVector& weights’ shadows a parameter [-Wshadow]
visp/modules/vision/src/plane-estimation/vpPlaneEstimation.cpp:77:58: warning: declaration of ‘const std::vector<double>& point_cloud’ shadows a parameter [-Wshadow]
visp/modules/vision/src/plane-estimation/vpPlaneEstimation.cpp:148:15: warning: declaration of ‘i’ shadows a previous local [-Wshadow]
visp/modules/vision/src/plane-estimation/vpPlaneEstimation.cpp:222:64: warning: declaration of ‘const vpPolygon& roi’ shadows a parameter [-Wshadow]
visp/modules/vision/src/plane-estimation/vpPlaneEstimation.cpp:235:62: warning: declaration of ‘const vpPolygon& roi’ shadows a parameter [-Wshadow]
visp/modules/vision/src/pose-estimation/vpPoseDementhon.cpp:439:21: warning: declaration of ‘i’ shadows a previous local [-Wshadow]
visp/modules/vision/src/pose-estimation/vpPoseDementhon.cpp:446:21: warning: declaration of ‘i’ shadows a previous local [-Wshadow]
visp/modules/vision/src/pose-estimation/vpPoseRGBD.cpp:233:12: warning: declaration of ‘point3d_size’ shadows a previous local [-Wshadow]
visp/modules/tracker/mbt/src/vpMbTracker.cpp:622:22: warning: declaration of ‘m_maxInitPoints’ shadows a member of ‘vpMbTracker’ [-Wshadow]
visp/modules/tracker/mbt/test/generic-with-dataset/perfGenericTracker.cpp:284:20: warning: declaration of ‘verbose’ shadows a previous local [-Wshadow]
visp/apps/calibration/intrinsic/visp-calibrate-camera.cpp:618:37: warning: declaration of ‘grid_points’ shadows a previous local [-Wshadow]
visp/example/tools/parallelPort.cpp:107:15: warning: declaration of ‘optarg’ shadows a global declaration [-Wshadow]
visp/example/tracking/mbtGenericTrackingDepth.cpp:766:31: warning: declaration of ‘ss’ shadows a previous local [-Wshadow]
visp/tutorial/computer-vision/tutorial-pose-from-planar-object.cpp:319:23: warning: declaration of ‘id’ shadows a previous local [-Wshadow]
visp/tutorial/detection/tag/tutorial-apriltag-detector-live.cpp:457:27: warning: declaration of ‘ss’ shadows a previous local [-Wshadow]
visp/tutorial/detection/tag/tutorial-apriltag-detector-live.cpp:473:29: warning: declaration of ‘ss’ shadows a previous local [-Wshadow]
visp/tutorial/imgproc/brightness/tutorial-brightness-adjustment.cpp:207:21: warning: declaration of ‘I_color_gamma_correction’ shadows a previous local [-Wshadow]
visp/tutorial/imgproc/brightness/tutorial-brightness-adjustment.cpp:210:28: warning: declaration of ‘I_gray_gamma_correction’ shadows a previous local [-Wshadow]
visp/tutorial/mean-drift/tutorial-meandrift.cpp:447:24: warning: declaration of ‘signal’ shadows a previous local [-Wshadow]
visp/tutorial/particle-filter/tutorial-pf.cpp:751:23: warning: declaration of ‘i’ shadows a previous local [-Wshadow]
visp/tutorial/tracking/model-based/generic/tutorial-mb-generic-tracker-full.cpp:461:27: warning: declaration of ‘ss’ shadows a previous local [-Wshadow]
visp/tutorial/tracking/model-based/generic/tutorial-mb-generic-tracker-full.cpp:479:27: warning: declaration of ‘ss’ shadows a previous local [-Wshadow]
visp/tutorial/tracking/model-based/generic/tutorial-mb-generic-tracker-full.cpp:513:27: warning: declaration of ‘ss’ shadows a previous local [-Wshadow]
visp/tutorial/tracking/model-based/generic-rgbd/tutorial-mb-generic-tracker-rgbd-realsense-json.cpp:116:19: warning: declaration of ‘config’ shadows a previous local [-Wshadow]