diff --git a/matlab/src/bits/impl/copy_gpu.cu b/matlab/src/bits/impl/copy_gpu.cu
index 204b1e95..e24f41ec 100644
--- a/matlab/src/bits/impl/copy_gpu.cu
+++ b/matlab/src/bits/impl/copy_gpu.cu
@@ -15,7 +15,7 @@ the terms of the BSD license (see the COPYING file).
 #include <string.h>
 
 template<typename type> __global__ void
-fill_kernel (type * data, type value, size_t size)
+fill_kernel (type * data, size_t size, type value)
 {
   int index = threadIdx.x + blockIdx.x * blockDim.x ;
   if (index < size) data[index] = value ;