Made cmake avoid using the Intel MKL when building mex files since it will

often create a conflict with MATLAB's copy of the MKL.

dlib/cmake_find_blas.txt

@@ -47,40 +47,43 @@ if (UNIX)
    include(CheckLibraryExists)
 
 
-   # Search for the needed libraries from the MKL.  We will try to link against the mkl_rt
-   # file first since this way avoids linking bugs in some cases.
-   find_library(mkl_rt mkl_rt ${mkl_search_path})
-   mark_as_advanced(  mkl_rt )
-   # if we found the MKL 
-   if ( mkl_rt)
-      set(blas_libraries  ${mkl_rt} )
-      set(lapack_libraries  ${mkl_rt} )
-      set(blas_found 1)
-      set(lapack_found 1)
-      set(found_intel_mkl 1)
-      message(STATUS "Found Intel MKL BLAS/LAPACK library")
-   endif()
-
-
-
-   if (NOT found_intel_mkl)
-      # Search for the needed libraries from the MKL.  This time try looking for a different
-      # set of MKL files and try to link against those.
-      find_library(mkl_core mkl_core ${mkl_search_path})
-      find_library(mkl_thread mkl_intel_thread ${mkl_search_path})
-      find_library(mkl_iomp iomp5 ${mkl_search_path})
-      find_library(mkl_pthread pthread ${mkl_search_path})
+   # Don't try to use the Intel MKL when we are building a MATLAB mex file
+   # since it will usually conflict with MATLAB's copy of the MKL and cause
+   # problems.
+   if (NOT BUILDING_MATLAB_MEX_FILE)
+        # Search for the needed libraries from the MKL.  We will try to link against the mkl_rt
+        # file first since this way avoids linking bugs in some cases.
+        find_library(mkl_rt mkl_rt ${mkl_search_path})
+        mark_as_advanced(  mkl_rt )
+        # if we found the MKL 
+        if ( mkl_rt)
+            set(blas_libraries  ${mkl_rt} )
+            set(lapack_libraries  ${mkl_rt} )
+            set(blas_found 1)
+            set(lapack_found 1)
+            set(found_intel_mkl 1)
+            message(STATUS "Found Intel MKL BLAS/LAPACK library")
+        endif()
 
-      mark_as_advanced( mkl_intel mkl_core mkl_thread mkl_iomp mkl_pthread)
-      # If we found the MKL 
-      if (mkl_intel AND mkl_core AND mkl_thread AND mkl_iomp AND mkl_pthread)
-         set(blas_libraries ${mkl_intel} ${mkl_core} ${mkl_thread} ${mkl_iomp} ${mkl_pthread})
-         set(lapack_libraries ${mkl_intel} ${mkl_core} ${mkl_thread} ${mkl_iomp} ${mkl_pthread})
-         set(blas_found 1)
-         set(lapack_found 1)
-         set(found_intel_mkl 1)
-         message(STATUS "Found Intel MKL BLAS/LAPACK library")
-      endif()
+        if (NOT found_intel_mkl)
+            # Search for the needed libraries from the MKL.  This time try looking for a different
+            # set of MKL files and try to link against those.
+            find_library(mkl_core mkl_core ${mkl_search_path})
+            find_library(mkl_thread mkl_intel_thread ${mkl_search_path})
+            find_library(mkl_iomp iomp5 ${mkl_search_path})
+            find_library(mkl_pthread pthread ${mkl_search_path})
+
+            mark_as_advanced( mkl_intel mkl_core mkl_thread mkl_iomp mkl_pthread)
+            # If we found the MKL 
+            if (mkl_intel AND mkl_core AND mkl_thread AND mkl_iomp AND mkl_pthread)
+                set(blas_libraries ${mkl_intel} ${mkl_core} ${mkl_thread} ${mkl_iomp} ${mkl_pthread})
+                set(lapack_libraries ${mkl_intel} ${mkl_core} ${mkl_thread} ${mkl_iomp} ${mkl_pthread})
+                set(blas_found 1)
+                set(lapack_found 1)
+                set(found_intel_mkl 1)
+                message(STATUS "Found Intel MKL BLAS/LAPACK library")
+            endif()
+        endif()
    endif()
 
 
@@ -96,6 +99,7 @@ if (UNIX)
         /usr/lib/atlas
         /usr/lib/openblas-base
         /opt/OpenBLAS/lib
+        $ENV{OPENBLAS_HOME}/lib
         )
 
    INCLUDE (CheckFunctionExists)

dlib/matlab/cmake_mex_wrapper

@@ -5,6 +5,7 @@
 
 cmake_minimum_required(VERSION 2.8.4)
 
+set(BUILDING_MATLAB_MEX_FILE true)
 
 # Find MATLAB's include directory and needed libraries 
 find_program(MATLAB_EXECUTABLE matlab PATHS