Merge pull request #26585 from FantasqueX:clean-up-cmake-1

Clean up cmake after upgrading cmake_minimum_required to 3.13

cmake/FindCUDA.cmake

@@ -1091,12 +1091,6 @@ endfunction()
 ##############################################################################
 
 macro(CUDA_WRAP_SRCS cuda_target format generated_files)
-
-  # If CMake doesn't support separable compilation, complain
-  if(CUDA_SEPARABLE_COMPILATION AND CMAKE_VERSION VERSION_LESS "2.8.10.1")
-    message(SEND_ERROR "CUDA_SEPARABLE_COMPILATION isn't supported for CMake versions less than 2.8.10.1")
-  endif()
-
   # Set up all the command line flags here, so that they can be overridden on a per target basis.
 
   set(nvcc_flags "")

cmake/OpenCVCompilerOptions.cmake

@@ -379,7 +379,7 @@ endif()
 
 # Apply "-Wl,--as-needed" linker flags: https://github.com/opencv/opencv/issues/7001
 if(NOT OPENCV_SKIP_LINK_AS_NEEDED)
-  if(UNIX AND (NOT APPLE OR NOT CMAKE_VERSION VERSION_LESS "3.2"))
+  if(UNIX)
     set(_option "-Wl,--as-needed")
     set(_saved_CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS}")
     set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${_option}")  # requires CMake 3.2+ and CMP0056
@@ -395,7 +395,7 @@ endif()
 
 # Apply "-Wl,--no-undefined" linker flags: https://github.com/opencv/opencv/pull/21347
 if(NOT OPENCV_SKIP_LINK_NO_UNDEFINED)
-  if(UNIX AND ((NOT APPLE OR NOT CMAKE_VERSION VERSION_LESS "3.2") AND NOT CMAKE_SYSTEM_NAME MATCHES "OpenBSD"))
+  if(UNIX AND (NOT CMAKE_SYSTEM_NAME MATCHES "OpenBSD"))
     set(_option "-Wl,--no-undefined")
     set(_saved_CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS}")
     set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${_option}")  # requires CMake 3.2+ and CMP0056

cmake/OpenCVDetectCUDA.cmake

@@ -14,9 +14,7 @@ if(CUDA_TOOLKIT_ROOT_DIR)
   set(CUDA_TOOLKIT_TARGET_DIR ${CUDA_TOOLKIT_ROOT_DIR})
 endif()
 
-if(((NOT CMAKE_VERSION VERSION_LESS "3.9.0")  # requires https://gitlab.kitware.com/cmake/cmake/merge_requests/663
+if(NOT OPENCV_CUDA_FORCE_BUILTIN_CMAKE_MODULE)
-      OR OPENCV_CUDA_FORCE_EXTERNAL_CMAKE_MODULE)
-    AND NOT OPENCV_CUDA_FORCE_BUILTIN_CMAKE_MODULE)
   ocv_update(CUDA_LINK_LIBRARIES_KEYWORD "PRIVATE")
   find_host_package(CUDA "${MIN_VER_CUDA}" QUIET)
 else()

cmake/OpenCVDetectCUDAUtils.cmake

@@ -113,9 +113,7 @@ macro(ocv_initialize_nvidia_device_generations)
     list(APPEND _generations "Auto")
   endif()
   set(CUDA_GENERATION "" CACHE STRING "Build CUDA device code only for specific GPU architecture. Leave empty to build for all architectures (see https://docs.opencv.org/5.x/d2/dbc/cuda_intro.html).")
-  if( CMAKE_VERSION VERSION_GREATER "2.8" )
   set_property( CACHE CUDA_GENERATION PROPERTY STRINGS "" ${_generations} )
-  endif()
 
   if(CUDA_GENERATION)
     if(NOT ";${_generations};" MATCHES ";${CUDA_GENERATION};")

cmake/OpenCVDetectPython.cmake

@@ -84,16 +84,12 @@ if(NOT ${found})
                         "Consider providing the '${executable}' variable via CMake command line or environment variables\n")
       endif()
       ocv_clear_vars(PYTHONINTERP_FOUND PYTHON_EXECUTABLE PYTHON_VERSION_STRING PYTHON_VERSION_MAJOR PYTHON_VERSION_MINOR PYTHON_VERSION_PATCH)
-      if(NOT CMAKE_VERSION VERSION_LESS "3.12")
       set(__PYTHON_PREFIX Python3)
       find_host_package(${__PYTHON_PREFIX} "${preferred_version}" COMPONENTS Interpreter)
       if(${__PYTHON_PREFIX}_EXECUTABLE)
         set(PYTHON_EXECUTABLE "${${__PYTHON_PREFIX}_EXECUTABLE}")
         find_host_package(PythonInterp "${preferred_version}")  # Populate other variables
       endif()
-      else()
-        message(STATUS "Consider using CMake 3.12+ for better Python support")
-      endif()
     endif()
     if(PYTHONINTERP_FOUND AND "${_python_version_major}" STREQUAL "${PYTHON_VERSION_MAJOR}")
       # Copy outputs

cmake/OpenCVFindIPP.cmake

@@ -168,13 +168,9 @@ macro(ipp_detect_version)
               )
               AND NOT OPENCV_SKIP_IPP_EXCLUDE_LIBS_CORE
           )
-            if(CMAKE_VERSION VERSION_LESS "3.13.0")
-              set(CMAKE_SHARED_LINKER_FLAGS "-Wl,--exclude-libs,${_filename} ${CMAKE_SHARED_LINKER_FLAGS}")
-            else()
             target_link_options(ipp${name} INTERFACE "LINKER:--exclude-libs,${_filename}")
           endif()
         endif()
-        endif()
         list(APPEND IPP_LIBRARIES ipp${name})
         if (NOT BUILD_SHARED_LIBS AND (HAVE_IPP_ICV OR ";${OPENCV_INSTALL_EXTERNAL_DEPENDENCIES};" MATCHES ";ipp;"))
           # CMake doesn't support "install(TARGETS ${IPP_PREFIX}${name} " command with imported targets

cmake/OpenCVFindLibsPerf.cmake

@@ -55,10 +55,7 @@ endif(WITH_CUDA)
 
 # --- Eigen ---
 if(WITH_EIGEN AND NOT HAVE_EIGEN)
-  if((OPENCV_FORCE_EIGEN_FIND_PACKAGE_CONFIG
+  if(NOT OPENCV_SKIP_EIGEN_FIND_PACKAGE_CONFIG)
-      OR NOT (CMAKE_VERSION VERSION_LESS "3.0.0")  # Eigen3Targets.cmake required CMake 3.0.0+
-      ) AND NOT OPENCV_SKIP_EIGEN_FIND_PACKAGE_CONFIG
-  )
     find_package(Eigen3 CONFIG QUIET)  # Ceres 2.0.0 CMake scripts doesn't work with CMake's FindEigen3.cmake module (due to missing EIGEN3_VERSION_STRING)
   endif()
   if(NOT Eigen3_FOUND)

cmake/OpenCVUtils.cmake

@@ -373,7 +373,7 @@ function(ocv_target_include_directories target)
       endif()
     endif()
   endforeach()
-  if(HAVE_CUDA OR CMAKE_VERSION VERSION_LESS 2.8.11)
+  if(HAVE_CUDA)
     include_directories(${__params})
     include_directories(SYSTEM ${__system_params})
   else()
@@ -915,15 +915,9 @@ if(DEFINED ENV{BUILD_USE_SYMLINKS})
 endif()
 OCV_OPTION(BUILD_USE_SYMLINKS "Use symlinks instead of files copying during build (and !!INSTALL!!)" (${__symlink_default}) IF (UNIX OR DEFINED __symlink_default))
 
-if(CMAKE_VERSION VERSION_LESS "3.2")
+macro(ocv_cmake_byproducts var_name)
-  macro(ocv_cmake_byproducts var_name)
-    set(${var_name}) # nothing
-  endmacro()
-else()
-  macro(ocv_cmake_byproducts var_name)
   set(${var_name} BYPRODUCTS ${ARGN})
-  endmacro()
+endmacro()
-endif()
 
 set(OPENCV_DEPHELPER "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/dephelper" CACHE INTERNAL "")
 file(MAKE_DIRECTORY ${OPENCV_DEPHELPER})
@@ -1267,13 +1261,8 @@ function(ocv_install_target)
 
     # don't move this into global scope of this file: compiler settings (like MSVC variable) are not available during processing
     if(BUILD_SHARED_LIBS)  # no defaults for static libs (modern CMake is required)
-      if(NOT CMAKE_VERSION VERSION_LESS 3.6.0)
       option(INSTALL_PDB_COMPONENT_EXCLUDE_FROM_ALL "Don't install PDB files by default" ON)
       option(INSTALL_PDB "Add install PDB rules" ON)
-      elseif(NOT CMAKE_VERSION VERSION_LESS 3.1.0)
-        option(INSTALL_PDB_COMPONENT_EXCLUDE_FROM_ALL "Don't install PDB files by default (not supported)" OFF)
-        option(INSTALL_PDB "Add install PDB rules" OFF)
-      endif()
     endif()
 
     if(INSTALL_PDB AND NOT INSTALL_IGNORE_PDB
@@ -1305,18 +1294,13 @@ function(ocv_install_target)
 
 #      message(STATUS "Process ${__target} dst=${__dst}...")
       if(DEFINED __dst)
-        if(NOT CMAKE_VERSION VERSION_LESS 3.1.0)
         set(__pdb_install_component "pdb")
         if(DEFINED INSTALL_PDB_COMPONENT AND INSTALL_PDB_COMPONENT)
           set(__pdb_install_component "${INSTALL_PDB_COMPONENT}")
         endif()
         set(__pdb_exclude_from_all "")
         if(INSTALL_PDB_COMPONENT_EXCLUDE_FROM_ALL)
-            if(NOT CMAKE_VERSION VERSION_LESS 3.6.0)
           set(__pdb_exclude_from_all EXCLUDE_FROM_ALL)
-            else()
-              message(WARNING "INSTALL_PDB_COMPONENT_EXCLUDE_FROM_ALL requires CMake 3.6+")
-            endif()
         endif()
 
 #          message(STATUS "Adding PDB file installation rule: target=${__target} dst=${__dst} component=${__pdb_install_component}")
@@ -1333,9 +1317,6 @@ function(ocv_install_target)
               DESTINATION "${__dst}" CONFIGURATIONS Release
               COMPONENT ${__pdb_install_component} OPTIONAL ${__pdb_exclude_from_all})
         endif()
-        else()
-          message(WARNING "PDB files installation is not supported (need CMake >= 3.1.0)")
-        endif()
       endif()
     endif()
   endif()
@@ -1628,45 +1609,19 @@ function(ocv_add_external_target name inc link def)
   endif()
   add_library(ocv.3rdparty.${name} INTERFACE ${imp})
   if(def)
-    if(NOT (CMAKE_VERSION VERSION_LESS "3.11.0"))  # https://gitlab.kitware.com/cmake/cmake/-/merge_requests/1264 : eliminates "Cannot specify compile definitions for imported target" error message
     target_compile_definitions(ocv.3rdparty.${name} INTERFACE "${def}")
-    else()
-      set_target_properties(ocv.3rdparty.${name} PROPERTIES INTERFACE_COMPILE_DEFINITIONS "${def}")
-    endif()
   endif()
   if(inc)
-    if(NOT (CMAKE_VERSION VERSION_LESS "3.11.0"))  # https://gitlab.kitware.com/cmake/cmake/-/merge_requests/1264 : eliminates "Cannot specify compile definitions for imported target" error message
     target_include_directories(ocv.3rdparty.${name} SYSTEM INTERFACE "$<BUILD_INTERFACE:${inc}>")
-    else()
-      set_target_properties(ocv.3rdparty.${name} PROPERTIES
-          INTERFACE_INCLUDE_DIRECTORIES "$<BUILD_INTERFACE:${inc}>"
-          INTERFACE_SYSTEM_INCLUDE_DIRECTORIES "$<BUILD_INTERFACE:${inc}>"
-      )
-    endif()
   endif()
   if(link)
-    # When cmake version is greater than or equal to 3.11, INTERFACE_LINK_LIBRARIES no longer applies to interface library
-    # See https://github.com/opencv/opencv/pull/18658
-    if(CMAKE_VERSION VERSION_LESS 3.11)
-      set_target_properties(ocv.3rdparty.${name} PROPERTIES
-        INTERFACE_LINK_LIBRARIES "${link}")
-    else()
     target_link_libraries(ocv.3rdparty.${name} INTERFACE ${link})
   endif()
-  endif()
-  # to install used target only upgrade CMake
-  if(NOT BUILD_SHARED_LIBS
-      AND CMAKE_VERSION VERSION_LESS "3.13.0"  # https://gitlab.kitware.com/cmake/cmake/-/merge_requests/2152
-  )
-    install(TARGETS ocv.3rdparty.${name} EXPORT OpenCVModules)
-  endif()
 endfunction()
 
 set(__OPENCV_EXPORTED_EXTERNAL_TARGETS "" CACHE INTERNAL "")
 function(ocv_install_used_external_targets)
-  if(NOT BUILD_SHARED_LIBS
+  if(NOT BUILD_SHARED_LIBS)
-      AND NOT (CMAKE_VERSION VERSION_LESS "3.13.0")  # upgrade CMake: https://gitlab.kitware.com/cmake/cmake/-/merge_requests/2152
-  )
     foreach(tgt in ${ARGN})
       if(tgt MATCHES "^ocv\.3rdparty\.")
         list(FIND __OPENCV_EXPORTED_EXTERNAL_TARGETS "${tgt}" _found)
@@ -1784,7 +1739,7 @@ endmacro()
 
 
 function(ocv_add_test_from_target test_name test_kind the_target)
-  if(CMAKE_VERSION VERSION_GREATER "2.8" AND NOT CMAKE_CROSSCOMPILING)
+  if(NOT CMAKE_CROSSCOMPILING)
     if(NOT "${test_kind}" MATCHES "^(Accuracy|Performance|Sanity)$")
       message(FATAL_ERROR "Unknown test kind : ${test_kind}")
     endif()
@@ -1979,12 +1934,7 @@ macro(ocv_get_smart_file_name output_var fpath)
 endmacro()
 
 # Needed by install(DIRECTORY ...)
-if(NOT CMAKE_VERSION VERSION_LESS 3.1)
+set(compatible_MESSAGE_NEVER MESSAGE_NEVER)
-  set(compatible_MESSAGE_NEVER MESSAGE_NEVER)
-else()
-  set(compatible_MESSAGE_NEVER "")
-endif()
-
 
 macro(ocv_git_describe var_name path)
   if(GIT_FOUND)

modules/core/cmake/parallel/detect_openmp.cmake

@@ -1,7 +1,3 @@
-if(CMAKE_VERSION VERSION_LESS "3.9")
-  message(STATUS "OpenMP detection requires CMake 3.9+")  # OpenMP::OpenMP_CXX target
-endif()
-
 find_package(OpenMP)
 if(OpenMP_FOUND)
   if(TARGET OpenMP::OpenMP_CXX)

samples/cpp/CMakeLists.txt

@@ -71,11 +71,9 @@ endforeach()
 include("tutorial_code/calib3d/real_time_pose_estimation/CMakeLists.txt" OPTIONAL)
 
 # Standalone samples only
-if(OpenCV_FOUND AND NOT CMAKE_VERSION VERSION_LESS "3.1")
+if(OpenCV_FOUND)
   add_subdirectory("example_cmake")
 endif()
-if(OpenCV_FOUND AND NOT CMAKE_VERSION VERSION_LESS "3.9"
+if(OpenCV_FOUND AND NOT OPENCV_EXAMPLES_SKIP_PARALLEL_BACKEND)
-    AND NOT OPENCV_EXAMPLES_SKIP_PARALLEL_BACKEND
-)
   add_subdirectory("tutorial_code/core/parallel_backend")
 endif()

samples/opencl/CMakeLists.txt

@@ -1,11 +1,5 @@
 ocv_install_example_src(opencl *.cpp *.hpp CMakeLists.txt)
 
-# cmake 3.1 needed for find_package(OpenCL)
-if(CMAKE_VERSION VERSION_LESS "3.1")
-  message(STATUS "OpenCL samples require CMakes 3.1+")
-  return()
-endif()
-
 set(OPENCV_OPENCL_SAMPLES_REQUIRED_DEPS
   opencv_core
   opencv_imgproc

samples/sycl/CMakeLists.txt

@@ -16,13 +16,6 @@ if(NOT BUILD_EXAMPLES OR NOT OCV_DEPENDENCIES_FOUND OR OPENCV_SKIP_SAMPLES_BUILD
   return()
 endif()
 
-if(CMAKE_VERSION VERSION_LESS "3.5")
-  message(STATUS "SYCL samples require CMake 3.5+")
-  return()
-endif()
-
-cmake_policy(VERSION 3.5)
-
 find_package(SYCL QUIET)  # will oneAPI support this straightforward way?
 
 if(NOT SYCL_FOUND AND NOT OPENCV_SKIP_SAMPLES_SYCL_ONEDNN)