don't print info message in verbose mode that is not needed.

theano/sandbox/cuda/blas.py

@@ -363,7 +363,7 @@ class GpuConv(Op):
         return ['cuda_ndarray.cuh','<stdio.h>']
 
     def c_code_cache_version(self):
-        return (0,11) # raise this whenever modifying any of the support_code_files
+        return (0,12) # raise this whenever modifying any of the support_code_files
 
     def c_support_code_apply(self, node, nodename):
         # REMEMBER TO RAISE c_code_cache_version when changing any of these files

theano/sandbox/cuda/conv.cu

@@ -1108,7 +1108,7 @@ CudaNdarray_Conv(CudaNdarray *img, CudaNdarray * kern,
     }
     else
     {
-      if (verbose) fprintf(stderr, "INFO: Conv is ignoring 'out' argument with wrong structure.\n");
+      if (out && verbose) fprintf(stderr, "INFO: Conv is ignoring 'out' argument with wrong structure.\n");
       rval = (CudaNdarray*)CudaNdarray_NewDims(4,out_dim);
       //rval might be null
     }