added global var to rng_mrg to suppress repeated warnings.

theano/sandbox/rng_mrg.py

@@ -376,6 +376,7 @@ class GPU_mrg_uniform(mrg_uniform_base):
             otype = 'double'
             NORM = '4.656612873077392578125e-10'
         return """
+        static int %(nodename)s_printed_warning = 0;
 
         static __global__ void %(nodename)s_mrg_uniform(
                 %(otype)s*sample_data,
@@ -543,7 +544,9 @@ class GPU_mrg_uniform(mrg_uniform_base):
 
             if (threads_per_block * n_blocks < n_streams)
             {
-                fprintf(stderr, "WARNING: unused streams above %%i (Tune GPU_mrg get_n_streams)\\n", threads_per_block * n_blocks );
+                if (! %(nodename)s_printed_warning)
+                  fprintf(stderr, "WARNING: unused streams above %%i (Tune GPU_mrg get_n_streams)\\n", threads_per_block * n_blocks );
+                %(nodename)s_printed_warning = 1;
             }
             %(nodename)s_mrg_uniform<<<n_blocks,threads_per_block>>>(
                 CudaNdarray_DEV_DATA(%(o_sample)s),
@@ -565,7 +568,7 @@ class GPU_mrg_uniform(mrg_uniform_base):
         //////// </ code generated by mrg_uniform>
         """ %locals()
     def c_code_cache_version(self):
-        return (3,)
+        return (4,)
 
 class MRG_RandomStreams(object):
     """Module component with similar interface to numpy.random (numpy.random.RandomState)"""