Merge pull request #9215 from alalek:cmake_min_version

CMakeLists.txt

@@ -18,7 +18,7 @@ endif()
 include(cmake/OpenCVMinDepVersions.cmake)
 
 if(CMAKE_GENERATOR MATCHES Xcode AND XCODE_VERSION VERSION_GREATER 4.3)
-  cmake_minimum_required(VERSION 2.8.8 FATAL_ERROR)
+  cmake_minimum_required(VERSION 3.0 FATAL_ERROR)
 elseif(CMAKE_SYSTEM_NAME MATCHES WindowsPhone OR CMAKE_SYSTEM_NAME MATCHES WindowsStore)
   cmake_minimum_required(VERSION 3.1 FATAL_ERROR)
   #Required to resolve linker error issues due to incompatibility with CMake v3.0+ policies.

cmake/OpenCVMinDepVersions.cmake

-set(MIN_VER_CMAKE 2.8.7)
+set(MIN_VER_CMAKE 2.8.12.2)
 set(MIN_VER_CUDA 6.5)
 set(MIN_VER_PYTHON2 2.6)
 set(MIN_VER_PYTHON3 3.2)