Minor cmake change

cmake/OpenCVCompilerOptions.cmake

@@ -32,15 +32,15 @@ if(MINGW)
   # http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40838
   # here we are trying to workaround the problem
   include(CheckCXXCompilerFlag)
-#  CHECK_CXX_COMPILER_FLAG(-mstackrealign HAVE_STACKREALIGN_FLAG)
- # if(HAVE_STACKREALIGN_FLAG)
-  #  set(OPENCV_EXTRA_C_FLAGS "${OPENCV_EXTRA_C_FLAGS} -mstackrealign")
-  #else()
+  CHECK_CXX_COMPILER_FLAG(-mstackrealign HAVE_STACKREALIGN_FLAG)
+  if(HAVE_STACKREALIGN_FLAG)
+    set(OPENCV_EXTRA_C_FLAGS "${OPENCV_EXTRA_C_FLAGS} -mstackrealign")
+  else()
     CHECK_CXX_COMPILER_FLAG(-mpreferred-stack-boundary=2 HAVE_PREFERRED_STACKBOUNDARY_FLAG)
     if(HAVE_PREFERRED_STACKBOUNDARY_FLAG)
       set(OPENCV_EXTRA_C_FLAGS "${OPENCV_EXTRA_C_FLAGS} -mstackrealign")
     endif()
-  #endif()
+  endif()
 endif()
 
 if(CMAKE_COMPILER_IS_GNUCXX)

cmake/OpenCVDetectCXXCompiler.cmake

@@ -8,11 +8,11 @@ endif()
 if(NOT APPLE)
   if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
     set(CMAKE_COMPILER_IS_GNUCXX 1)
-    unset(ENABLE_PRECOMPILED_HEADERS CACHE)
+    set(ENABLE_PRECOMPILED_HEADERS OFF CACHE BOOL "" FORCE)
   endif()
   if(CMAKE_C_COMPILER_ID STREQUAL "Clang")
     set(CMAKE_COMPILER_IS_GNUCC 1)
-    unset(ENABLE_PRECOMPILED_HEADERS CACHE)
+    set(ENABLE_PRECOMPILED_HEADERS OFF CACHE BOOL "" FORCE)
   endif()
 endif()