diff --git a/android/android.toolchain.cmake b/android/android.toolchain.cmake
index dc33fc924d..4f5854069c 100644
--- a/android/android.toolchain.cmake
+++ b/android/android.toolchain.cmake
@@ -766,30 +766,30 @@ set( CMAKE_COMPILER_IS_GNUASM 1)
 # NDK flags
 if( ARMEABI OR ARMEABI_V7A )
  # NDK also defines -ffunction-sections -funwind-tables but they result in worse OpenCV performance
- set( CMAKE_CXX_FLAGS "-fPIC -Wno-psabi" )
- set( CMAKE_C_FLAGS "-fPIC -Wno-psabi" )
+ set( _CMAKE_CXX_FLAGS "-fPIC -Wno-psabi" )
+ set( _CMAKE_C_FLAGS "-fPIC -Wno-psabi" )
  remove_definitions( -D__ARM_ARCH_5__ -D__ARM_ARCH_5T__ -D__ARM_ARCH_5E__ -D__ARM_ARCH_5TE__ )
  add_definitions( -D__ARM_ARCH_5__ -D__ARM_ARCH_5T__ -D__ARM_ARCH_5E__ -D__ARM_ARCH_5TE__ )
  # extra arm-specific flags
  set( ANDROID_CXX_FLAGS "${ANDROID_CXX_FLAGS} -fsigned-char" )
 elseif( X86 )
- set( CMAKE_CXX_FLAGS "-funwind-tables" )
- set( CMAKE_C_FLAGS "-funwind-tables" )
+ set( _CMAKE_CXX_FLAGS "-funwind-tables" )
+ set( _CMAKE_C_FLAGS "-funwind-tables" )
 elseif( MIPS )
- set( CMAKE_CXX_FLAGS "-fpic -Wno-psabi -fno-strict-aliasing -finline-functions -ffunction-sections -funwind-tables -fmessage-length=0 -fno-inline-functions-called-once -fgcse-after-reload -frerun-cse-after-loop -frename-registers" )
- set( CMAKE_CXX_FLAGS "-fpic -Wno-psabi -fno-strict-aliasing -finline-functions -ffunction-sections -funwind-tables -fmessage-length=0 -fno-inline-functions-called-once -fgcse-after-reload -frerun-cse-after-loop -frename-registers" )
+ set( _CMAKE_CXX_FLAGS "-fpic -Wno-psabi -fno-strict-aliasing -finline-functions -ffunction-sections -funwind-tables -fmessage-length=0 -fno-inline-functions-called-once -fgcse-after-reload -frerun-cse-after-loop -frename-registers" )
+ set( _CMAKE_CXX_FLAGS "-fpic -Wno-psabi -fno-strict-aliasing -finline-functions -ffunction-sections -funwind-tables -fmessage-length=0 -fno-inline-functions-called-once -fgcse-after-reload -frerun-cse-after-loop -frename-registers" )
  set( ANDROID_CXX_FLAGS "${ANDROID_CXX_FLAGS} -fsigned-char" )
 else()
- set( CMAKE_CXX_FLAGS "" )
- set( CMAKE_C_FLAGS "" )
+ set( _CMAKE_CXX_FLAGS "" )
+ set( _CMAKE_C_FLAGS "" )
 endif()
 
 if( ANDROID_USE_STLPORT )
- set( CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-rtti -fno-exceptions" )
- set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fno-rtti -fno-exceptions" )
+ set( _CMAKE_CXX_FLAGS "${_CMAKE_CXX_FLAGS} -fno-rtti -fno-exceptions" )
+ set( _CMAKE_C_FLAGS "${_CMAKE_C_FLAGS} -fno-rtti -fno-exceptions" )
 else()
- set( CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -frtti -fexceptions" )
- set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fexceptions" )
+ set( _CMAKE_CXX_FLAGS "${_CMAKE_CXX_FLAGS} -frtti -fexceptions" )
+ set( _CMAKE_C_FLAGS "${_CMAKE_C_FLAGS} -fexceptions" )
 endif()
 
 #release and debug flags
@@ -798,33 +798,33 @@ if( ARMEABI OR ARMEABI_V7A )
   #It is recommended to use the -mthumb compiler flag to force the generation
   #of 16-bit Thumb-1 instructions (the default being 32-bit ARM ones).
   # O3 instead of O2/Os in release mode - like cmake sets for desktop gcc
-  set( CMAKE_CXX_FLAGS_RELEASE "-mthumb -O3" )
-  set( CMAKE_C_FLAGS_RELEASE   "-mthumb -O3" )
-  set( CMAKE_CXX_FLAGS_DEBUG "-marm -Os -finline-limit=64" )
-  set( CMAKE_C_FLAGS_DEBUG   "-marm -Os -finline-limit=64" )
+  set( _CMAKE_CXX_FLAGS_RELEASE "-mthumb -O3" )
+  set( _CMAKE_C_FLAGS_RELEASE   "-mthumb -O3" )
+  set( _CMAKE_CXX_FLAGS_DEBUG "-marm -Os -finline-limit=64" )
+  set( _CMAKE_C_FLAGS_DEBUG   "-marm -Os -finline-limit=64" )
  else()
   # always compile ARMEABI_V6 in arm mode; otherwise there is no difference from ARMEABI
   # O3 instead of O2/Os in release mode - like cmake sets for desktop gcc
-  set( CMAKE_CXX_FLAGS_RELEASE "-marm -O3 -fstrict-aliasing" )
-  set( CMAKE_C_FLAGS_RELEASE   "-marm -O3 -fstrict-aliasing" )
-  set( CMAKE_CXX_FLAGS_DEBUG "-marm -O0 -finline-limit=300" )
-  set( CMAKE_C_FLAGS_DEBUG   "-marm -O0 -finline-limit=300" )
+  set( _CMAKE_CXX_FLAGS_RELEASE "-marm -O3 -fstrict-aliasing" )
+  set( _CMAKE_C_FLAGS_RELEASE   "-marm -O3 -fstrict-aliasing" )
+  set( _CMAKE_CXX_FLAGS_DEBUG "-marm -O0 -finline-limit=300" )
+  set( _CMAKE_C_FLAGS_DEBUG   "-marm -O0 -finline-limit=300" )
  endif()
 elseif( X86 )
- set( CMAKE_CXX_FLAGS_RELEASE "-O3 -fstrict-aliasing" )
- set( CMAKE_C_FLAGS_RELEASE   "-O3 -fstrict-aliasing" )
- set( CMAKE_CXX_FLAGS_DEBUG "-O0 -finline-limit=300" )
- set( CMAKE_C_FLAGS_DEBUG   "-O0 -finline-limit=300" )
+ set( _CMAKE_CXX_FLAGS_RELEASE "-O3 -fstrict-aliasing" )
+ set( _CMAKE_C_FLAGS_RELEASE   "-O3 -fstrict-aliasing" )
+ set( _CMAKE_CXX_FLAGS_DEBUG "-O0 -finline-limit=300" )
+ set( _CMAKE_C_FLAGS_DEBUG   "-O0 -finline-limit=300" )
 elseif( MIPS )
- set( CMAKE_CXX_FLAGS_RELEASE "-O3 -funswitch-loops -finline-limit=300" )
- set( CMAKE_C_FLAGS_RELEASE   "-O3 -funswitch-loops -finline-limit=300" )
- set( CMAKE_CXX_FLAGS_DEBUG "-O0 -g" )
- set( CMAKE_C_FLAGS_DEBUG   "-O0 -g" )
+ set( _CMAKE_CXX_FLAGS_RELEASE "-O3 -funswitch-loops -finline-limit=300" )
+ set( _CMAKE_C_FLAGS_RELEASE   "-O3 -funswitch-loops -finline-limit=300" )
+ set( _CMAKE_CXX_FLAGS_DEBUG "-O0 -g" )
+ set( _CMAKE_C_FLAGS_DEBUG   "-O0 -g" )
 endif()
-set( CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -fomit-frame-pointer -DNDEBUG" )
-set( CMAKE_C_FLAGS_RELEASE   "${CMAKE_C_FLAGS_RELEASE}   -fomit-frame-pointer -DNDEBUG" )
-set( CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -fno-strict-aliasing -fno-omit-frame-pointer -DDEBUG -D_DEBUG" )
-set( CMAKE_C_FLAGS_DEBUG   "${CMAKE_C_FLAGS_DEBUG}   -fno-strict-aliasing -fno-omit-frame-pointer -DDEBUG -D_DEBUG" )
+set( _CMAKE_CXX_FLAGS_RELEASE "${_CMAKE_CXX_FLAGS_RELEASE} -fomit-frame-pointer -DNDEBUG" )
+set( _CMAKE_C_FLAGS_RELEASE   "${_CMAKE_C_FLAGS_RELEASE}   -fomit-frame-pointer -DNDEBUG" )
+set( _CMAKE_CXX_FLAGS_DEBUG "${_CMAKE_CXX_FLAGS_DEBUG} -fno-strict-aliasing -fno-omit-frame-pointer -DDEBUG -D_DEBUG" )
+set( _CMAKE_C_FLAGS_DEBUG   "${_CMAKE_C_FLAGS_DEBUG}   -fno-strict-aliasing -fno-omit-frame-pointer -DDEBUG -D_DEBUG" )
 
 #ABI-specific flags
 if( ARMEABI_V7A )
@@ -928,12 +928,12 @@ if( ARMEABI_V7A )
 endif()
 
 #cache flags
-set( CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}" CACHE STRING "c++ flags" )
-set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS}" CACHE STRING "c flags" )
-set( CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE}" CACHE STRING "c++ Release flags" )
-set( CMAKE_C_FLAGS_RELEASE "${CMAKE_C_FLAGS_RELEASE}" CACHE STRING "c Release flags" )
-set( CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG}" CACHE STRING "c++ Debug flags" )
-set( CMAKE_C_FLAGS_DEBUG "${CMAKE_C_FLAGS_DEBUG}" CACHE STRING "c Debug flags" )
+set( CMAKE_CXX_FLAGS "${_CMAKE_CXX_FLAGS}" CACHE STRING "c++ flags" )
+set( CMAKE_C_FLAGS "${_CMAKE_C_FLAGS}" CACHE STRING "c flags" )
+set( CMAKE_CXX_FLAGS_RELEASE "${_CMAKE_CXX_FLAGS_RELEASE}" CACHE STRING "c++ Release flags" )
+set( CMAKE_C_FLAGS_RELEASE "${_CMAKE_C_FLAGS_RELEASE}" CACHE STRING "c Release flags" )
+set( CMAKE_CXX_FLAGS_DEBUG "${_CMAKE_CXX_FLAGS_DEBUG}" CACHE STRING "c++ Debug flags" )
+set( CMAKE_C_FLAGS_DEBUG "${_CMAKE_C_FLAGS_DEBUG}" CACHE STRING "c Debug flags" )
 set( CMAKE_SHARED_LINKER_FLAGS "" CACHE STRING "linker flags" )
 set( CMAKE_MODULE_LINKER_FLAGS "" CACHE STRING "linker flags" )
 set( CMAKE_EXE_LINKER_FLAGS "-Wl,-z,nocopyreloc" CACHE STRING "linker flags" )
diff --git a/cmake/OpenCVDetectPython.cmake b/cmake/OpenCVDetectPython.cmake
index e025a7fd2c..59513ad480 100644
--- a/cmake/OpenCVDetectPython.cmake
+++ b/cmake/OpenCVDetectPython.cmake
@@ -12,12 +12,10 @@ if(MSVC AND NOT PYTHON_EXECUTABLE)
     )
   endforeach()
 endif()
-
 find_host_package(PythonInterp 2.0)
 
 unset(PYTHON_USE_NUMPY CACHE)
 unset(HAVE_SPHINX CACHE)
-
 if(PYTHON_EXECUTABLE)
   if(PYTHON_VERSION_STRING)
     set(PYTHON_VERSION_MAJOR_MINOR "${PYTHON_VERSION_MAJOR}.${PYTHON_VERSION_MINOR}")
@@ -46,16 +44,15 @@ if(PYTHON_EXECUTABLE)
                       OUTPUT_VARIABLE PYTHON_STD_PACKAGES_PATH
                       OUTPUT_STRIP_TRAILING_WHITESPACE)
       if("${PYTHON_STD_PACKAGES_PATH}" MATCHES "site-packages")
-        set(PYTHON_PACKAGES_PATH "python${PYTHON_VERSION_MAJOR_MINOR}/site-packages")
+        set(_PYTHON_PACKAGES_PATH "python${PYTHON_VERSION_MAJOR_MINOR}/site-packages")
       else() #debian based assumed, install to the dist-packages.
-        set(PYTHON_PACKAGES_PATH "python${PYTHON_VERSION_MAJOR_MINOR}/dist-packages")
+        set(_PYTHON_PACKAGES_PATH "python${PYTHON_VERSION_MAJOR_MINOR}/dist-packages")
       endif()
       if(EXISTS "${CMAKE_INSTALL_PREFIX}/lib${LIB_SUFFIX}/${PYTHON_PACKAGES_PATH}")
-        set(PYTHON_PACKAGES_PATH "lib${LIB_SUFFIX}/${PYTHON_PACKAGES_PATH}")
+        set(_PYTHON_PACKAGES_PATH "lib${LIB_SUFFIX}/${_PYTHON_PACKAGES_PATH}")
       else()
-        set(PYTHON_PACKAGES_PATH "lib/${PYTHON_PACKAGES_PATH}")
+        set(_PYTHON_PACKAGES_PATH "lib/${_PYTHON_PACKAGES_PATH}")
       endif()
-      set(PYTHON_PACKAGES_PATH "${PYTHON_PACKAGES_PATH}" CACHE PATH "Where to install the python packages.")
     elseif(CMAKE_HOST_WIN32)
       get_filename_component(PYTHON_PATH "${PYTHON_EXECUTABLE}" PATH)
       file(TO_CMAKE_PATH "${PYTHON_PATH}" PYTHON_PATH)
@@ -67,8 +64,9 @@ if(PYTHON_EXECUTABLE)
         endif()
         file(TO_CMAKE_PATH "${PYTHON_PATH}" PYTHON_PATH)
       endif()
-      set(PYTHON_PACKAGES_PATH "${PYTHON_PATH}/Lib/site-packages")
+      set(_PYTHON_PACKAGES_PATH "${PYTHON_PATH}/Lib/site-packages")
     endif()
+    SET(PYTHON_PACKAGES_PATH "${_PYTHON_PACKAGES_PATH}" CACHE PATH "Where to install the python packages.")
 
     if(NOT PYTHON_NUMPY_INCLUDE_DIR)
       # Attempt to discover the NumPy include directory. If this succeeds, then build python API with NumPy
@@ -78,8 +76,8 @@ if(PYTHON_EXECUTABLE)
                       OUTPUT_STRIP_TRAILING_WHITESPACE)
                       
       if(PYTHON_NUMPY_PROCESS EQUAL 0)
-        file(TO_CMAKE_PATH "${PYTHON_NUMPY_INCLUDE_DIR}" PYTHON_NUMPY_INCLUDE_DIR)
-        set(PYTHON_NUMPY_INCLUDE_DIR ${PYTHON_NUMPY_INCLUDE_DIR} CACHE PATH "Path to numpy headers")
+        file(TO_CMAKE_PATH "${PYTHON_NUMPY_INCLUDE_DIR}" _PYTHON_NUMPY_INCLUDE_DIR)
+        set(PYTHON_NUMPY_INCLUDE_DIR ${_PYTHON_NUMPY_INCLUDE_DIR} CACHE PATH "Path to numpy headers")
       endif()
     endif()