Define new V4 elements from V3 elements in cudnn_helper (gpua backend)

theano/sandbox/gpuarray/cudnn_helper.h

@@ -125,5 +125,14 @@ static inline cudnnStatus_t cudnnSetConvolutionNdDescriptor_v3(
 
 #endif
 
+// If needed, define element of the V4 interface in terms of elements of
+// previous versions
+#if defined(CUDNN_VERSION) && CUDNN_VERSION < 4000
+
+#define CUDNN_CONVOLUTION_FWD_ALGO_FFT_TILING 5
+#define CUDNN_CONVOLUTION_BWD_FILTER_ALGO_3 3
+#define CUDNN_CONVOLUTION_BWD_DATA_ALGO_FFT_TILING 3
+
+#endif
 
 #endif