Checks inside Xcode for latest OSX SDK (BVLC#4840)

OS X: build with latest SDK by default

Makefile

@@ -192,12 +192,12 @@ ifeq ($(USE_LMDB), 1)
 	LIBRARIES += lmdb
 endif
 ifeq ($(USE_OPENCV), 1)
-	LIBRARIES += opencv_core opencv_highgui opencv_imgproc 
+	LIBRARIES += opencv_core opencv_highgui opencv_imgproc
 
 	ifeq ($(OPENCV_VERSION), 3)
 		LIBRARIES += opencv_imgcodecs
 	endif
-		
+
 endif
 PYTHON_LIBRARIES ?= boost_python python2.7
 WARNINGS := -Wall -Wno-sign-compare
@@ -385,7 +385,7 @@ else
 		XCODE_CLT_GEQ_7 := $(shell [ $(XCODE_CLT_VER) -gt 6 ] && echo 1)
 		XCODE_CLT_GEQ_6 := $(shell [ $(XCODE_CLT_VER) -gt 5 ] && echo 1)
 		ifeq ($(XCODE_CLT_GEQ_7), 1)
-			BLAS_INCLUDE ?= /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk/System/Library/Frameworks/Accelerate.framework/Versions/A/Frameworks/vecLib.framework/Versions/A/Headers
+			BLAS_INCLUDE ?= /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/$(shell ls /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/ | sort | tail -1)/System/Library/Frameworks/Accelerate.framework/Versions/A/Frameworks/vecLib.framework/Versions/A/Headers
 		else ifeq ($(XCODE_CLT_GEQ_6), 1)
 			BLAS_INCLUDE ?= /System/Library/Frameworks/Accelerate.framework/Versions/Current/Frameworks/vecLib.framework/Headers/
 			LDFLAGS += -framework Accelerate