fixed problem with building module gpu on linux

modules/gpu/CMakeLists.txt

@@ -5,11 +5,15 @@ if (CUDA_FOUND)
     include_directories(${CUDA_INCLUDE_DIRS})
     link_directories(${CUDA_LIBRARIES})
 
+    #message ("CUDA_LIBRARIES = ${CUDA_LIBRARIES}")
+    #message ("CUDA_INCLUDE_DIRS = ${CUDA_INCLUDE_DIRS}")
+    #message ("CUDA_TARGET_LINK = ${CUDA_TARGET_LINK}")
+
+
 	#CUDA_GENERATED_OUTPUT_DIR (Default CMAKE_CURRENT_BINARY_DIR)
 
 	#====================================================================================
 	
-	
 	set(name "gpu")	
 	set(DEPS "opencv_core")
 		
@@ -38,10 +42,16 @@ if (CUDA_FOUND)
 	file(GLOB lib_hdrs "include/opencv2/${name}/*.h*")		
 	source_group("Include" FILES ${lib_hdrs})
 
+        if (UNIX OR APPLE)
+            set (CUDA_NVCC_FLAGS "-Xcompiler;-fPIC")
+        endif()
+
 	CUDA_COMPILE(cuda_objs ${lib_cuda})
+        #message ("lib cuda : ${cuda_objs}")
 	#CUDA_BUILD_CLEAN_TARGET()
 		
 	set(the_target "opencv_${name}")
+        #message ("cuda_add_library : ${the_target} ${lib_srcs} ${lib_hdrs} ${lib_int_hdrs} ${lib_cuda} ${lib_cuda_hdrs}")
         add_library(${the_target} ${lib_srcs} ${lib_hdrs} ${lib_int_hdrs} ${lib_cuda} ${lib_cuda_hdrs} ${cuda_objs})
 
 	if(PCHSupport_FOUND)
@@ -72,6 +82,7 @@ if (CUDA_FOUND)
 		)
 
         # Add the required libraries for linking:
+        #message (" ++++ target_link_libraries = ${the_target} ${OPENCV_LINKER_LIBS} ${IPP_LIBS} ${DEPS} ${CUDA_LIBRARIES}")
 	target_link_libraries(${the_target} ${OPENCV_LINKER_LIBS} ${IPP_LIBS} ${DEPS} ${CUDA_LIBRARIES})
 
 	if(MSVC)