added unittest to trigger canonizer bug: tensor/tests/test_opt.py:test_add_canonizer_problem0

theano/tensor/opt.py

@@ -16,6 +16,8 @@ import itertools
 import sys
 from .. import compile  #to register the optimizer built by this file
 
+from ..compile.debugmode import _debugprint
+
 
 # Utilities
 
@@ -669,11 +671,13 @@ class Canonizer(gof.LocalOptimizer):
 
     def transform(self, node):
         op = node.op
-        inputs = node.inputs
-        out = node.outputs[0]
         if op not in [self.main, self.inverse, self.reciprocal]:
             return False
 
+        inputs = node.inputs
+        out = node.outputs[0]
+        assert len(node.outputs) == 1
+
         # I'm not sure if this is actually needed but the following
         # block of code puts into "reorg" whether or not we are going
         # to change the structure of the graph. For example if we have
@@ -714,6 +718,12 @@ class Canonizer(gof.LocalOptimizer):
         if new.type.broadcastable != out.type.broadcastable:
             new = T.fill(out, new)
 
+            if 0:
+                print 'BEFORE'
+                _debugprint(out, '  ', depth=4)
+                print 'AFTER'
+                _debugprint(new, '  ', depth=4)
+
         # if our if's above worked, this should be true. OTW investigate.
         if new.type != out.type:
             print >> sys.stderr, 'CANONIZE FAILED: new, out = ', new, ',', out, 'types', new.type, ',', out.type

theano/tensor/tests/test_opt.py

@@ -62,6 +62,15 @@ class test_dimshuffle_lift(unittest.TestCase):
         self.failUnless(str(g) == "[add(add(InplaceDimShuffle{x,x,0}(x), InplaceDimShuffle{x,0,1}(y)), z)]", str(g))
 
 
+def test_add_canonizer_problem0():
+    #observed in a real graph
+
+    n_segments = 10
+    label = lscalar('label')
+    segment_labels = label + numpy.asarray([0] * n_segments, dtype='int64')
+
+    r = segment_labels * 5
+    f = function([label], r)