Delete function that has now become unnecessary

dlib/CMakeLists.txt

@@ -22,15 +22,6 @@ if(has_parent)
    set(DLIB_VERSION ${VERSION} PARENT_SCOPE)
 endif()
 
-set(dlib_needed_includes)
-# This macro sets include directory paths that are needed by dlib and also by
-# applications that include dlib.  So the main point of this macro is to set
-# dlib_needed_includes which will get pushed into the parent cmake scope at the
-# end of this CMakeLists.txt file.  This way, it is available to users of dlib/cmake.
-macro(add_include_directories dir)
-   set(dlib_needed_includes ${dlib_needed_includes} ${dir})
-endmacro()
-
 # Suppress cmake warnings about changes in new versions.
 if(COMMAND cmake_policy) 
    cmake_policy(SET CMP0003 NEW) 
@@ -224,6 +215,7 @@ if (NOT TARGET dlib)
          )
 
       set(dlib_needed_libraries)
+      set(dlib_needed_includes)
       if(UNIX)
          set(CMAKE_THREAD_PREFER_PTHREAD ON)
          find_package(Threads REQUIRED)
@@ -331,7 +323,7 @@ if (NOT TARGET dlib)
       if (DLIB_GIF_SUPPORT)
          find_package(GIF QUIET)
          if (GIF_FOUND)
-            add_include_directories(${GIF_INCLUDE_DIR})
+            set (dlib_needed_includes ${dlib_needed_includes} ${GIF_INCLUDE_DIR})
             set (dlib_needed_libraries ${dlib_needed_libraries} ${GIF_LIBRARY})
          else()
             set(DLIB_GIF_SUPPORT OFF CACHE STRING ${DLIB_GIF_SUPPORT_STR} FORCE )
@@ -498,8 +490,8 @@ if (NOT TARGET dlib)
 
          if (DLIB_USE_MKL_FFT)
             if (found_intel_mkl AND found_intel_mkl_headers)
+               set (dlib_needed_includes ${dlib_needed_includes} ${mkl_include_dir})
                set (dlib_needed_libraries ${dlib_needed_libraries} ${mkl_libraries})
-               add_include_directories(${mkl_include_dir})
             else()
                set(DLIB_USE_MKL_FFT OFF CACHE STRING ${DLIB_USE_MKL_FFT_STR} FORCE )
                toggle_preprocessor_switch(DLIB_USE_MKL_FFT)
@@ -614,7 +606,7 @@ if (NOT TARGET dlib)
          find_path(sqlite_path sqlite3.h)
          if (sqlite AND sqlite_path)
             get_filename_component(sqlite_path2 ${sqlite_path} PATH CACHE)
-            add_include_directories(${sqlite_path2})
+            set(dlib_needed_includes ${dlib_needed_includes} ${sqlite_path2})
             set(dlib_needed_libraries ${dlib_needed_libraries} ${sqlite} )
          else()
             set(DLIB_LINK_WITH_SQLITE3 OFF CACHE STRING ${DLIB_LINK_WITH_SQLITE3_STR} FORCE )
@@ -629,7 +621,7 @@ if (NOT TARGET dlib)
          # make sure fftw3.h is in the include path
          find_path(fftw_path fftw3.h)
          if (fftw AND fftw_path)
-            add_include_directories(${fftw_path})
+            set(dlib_needed_includes ${dlib_needed_includes} ${fftw_path})
             set(dlib_needed_libraries ${dlib_needed_libraries} ${fftw} )
          else()
             set(DLIB_USE_FFTW OFF CACHE STRING ${DLIB_USE_FFTW_STR} FORCE )