Merge pull request #4984 from nouiz/mixed6

ISSUE_TEMPLATE.md

 If you have any questions on Theano, please ask your questions in either [theano-user mailing list](https://groups.google.com/forum/#!forum/theano-users) or [stackoverflow](http://stackoverflow.com/) with the "theano" tag.
 
 Use issue only to report bugs or to ask for new features in Theano.
+
+Before reporting a bug, update to Theano development version. Maybe it
+is already fixed. If not, tell us the Theano flags and Theano version
+that generate the problem. If it is a regression, can do a "git
+bisect" to idenfy when the problem appeard. This really help fix it
+rapidly.
+
+If you add a feature request, describe in which case it will be useful.
\ No newline at end of file

doc/dev_start_guide.txt

@@ -55,7 +55,7 @@ Requirements for Quality Contributions
 
 * All the code should be properly tested. 
 
-* The code should be compatible with Python 2.6 and above, as well as Python 
+* The code should be compatible with Python 2.7 and above, as well as Python
   3.3 and above (using `six` if needed).
 
 * All the code should respect the 

theano/configdefaults.py

@@ -442,12 +442,21 @@ if param != "":
 # to support path that includes spaces, we need to wrap it with double quotes on Windows
 if param and os.name == 'nt':
     param = '"%s"' % param
+
+
+def warn_cxx(val):
+    """We only support clang++ as otherwise we hit strange g++/OSX bugs."""
+    if sys.platform == 'darwin' and val != 'clang++':
+        _logger.warning("Only clang++ is supported. With g++,"
+                        " we end up with strange g++/OSX bugs.")
+    return True
+
 AddConfigVar('cxx',
              "The C++ compiler to use. Currently only g++ is"
              " supported, but supporting additional compilers should not be "
              "too difficult. "
              "If it is empty, no C++ code is compiled.",
-             StrParam(param),
+             StrParam(param, is_valid=warn_cxx),
              in_c_key=False)
 del param
 

theano/misc/do_nightly_build

@@ -36,6 +36,7 @@ if [ "$1" == "--buildbot" ]; then
     NOSETESTS=${ROOT_CWD}/Theano/bin/theano-nose
     export PYTHONPATH=${ROOT_CWD}:$PYTHONPATH
 else
+    ROOT_CWD=.
     COMPILEDIR=`python -c "from __future__ import print_function; import theano; print(theano.config.compiledir)"|tail -1`
     NOSETESTS=`python -c "from __future__ import print_function; import theano; print(theano.__path__[0])"|tail -1`/../bin/theano-nose
 fi

theano/sandbox/cuda/fftconv.py

 from __future__ import absolute_import, print_function, division
-import string
 
 import numpy as np
 import theano
@@ -247,8 +246,8 @@ def sc_complex_dot_batched(bx_gpu, by_gpu, bc_gpu, transa='N', transb='N',
     alpha = np.complex64(1.0)
     beta = np.complex64(0.0)
 
-    transa = string.lower(transa)
-    transb = string.lower(transb)
+    transa = transa.lower()
+    transb = transb.lower()
 
     if transb in ['t', 'c']:
         N, m, k = by_shape

theano/sandbox/cuda/opt.py

@@ -1672,7 +1672,7 @@ conv_groupopt.register('local_conv_dnn', dnn.local_conv_dnn,
 # It can be disabled by excluding 'conv_gemm'.
 conv_groupopt.register('local_conv_gemm', local_conv_gemm,
                        'conv_gemm',
-                       'fast_compile', 'fast_run', positin=30)
+                       'fast_compile', 'fast_run', position=30)
 
 
 class LocalCudaMetaOptimizer(LocalMetaOptimizer):

theano/tensor/opt.py

@@ -3069,14 +3069,10 @@ def local_subtensor_of_alloc(node):
     if type(rval) not in (list, tuple):
         rval = [rval]
     if rval[0].type != node.outputs[0].type:
-        # It happen that the make_node() isn't able to infer that some
-        # dimensions are broadcastable, but that now we can infer
-        # that. So we need to remove that information here.
-        rval[0] = theano.tensor.unbroadcast(
-            rval[0],
-            *[i for i, (b1, b2) in enumerate(zip(rval[0].broadcastable,
-                                                 node.outputs[0].broadcastable))
-              if b1 and not b2])
+        # It happen that the make_node() isn't able to infer the same pattern.
+        # We know it is safe, so fix that.
+        rval[0] = T.patternbroadcast(rval[0], node.outputs[0].broadcastable)
+
     return rval
 
 
@@ -4855,6 +4851,13 @@ class Canonizer(gof.LocalOptimizer):
         assert len(node.outputs) == 1
         out = node.outputs[0]
 
+        # out won't have a clients field when we didn't commit a
+        # started change in the graph.  We can't do the check if we
+        # want to skip it, so we force the skip it. It should be
+        # reapplied later.
+        if not hasattr(out, 'clients'):
+            return
+
         # check if any of the clients of this node would be part of
         # this canonized graph...  if so, we do nothing and wait for
         # them to be transformed.
@@ -5942,7 +5945,7 @@ def local_add_specialize(node):
 register_specialize(local_add_specialize)
 
 mul_canonizer = in2out(gof.LocalOptGroup(local_mul_canonizer, local_fill_cut,
-                                         local_fill_sink),
+                                         local_fill_sink, apply_all_opts=True),
                        name='mul_canonizer_groups')
 
 
@@ -6101,7 +6104,7 @@ def add_calculate(num, denum, aslist=False, out_type=None):
 
 local_add_canonizer = Canonizer(T.add, T.sub, T.neg, add_calculate)
 add_canonizer = in2out(gof.LocalOptGroup(local_add_canonizer, local_fill_cut,
-                                         local_fill_sink),
+                                         local_fill_sink, apply_all_opts=True),
                        name='add_canonizer_group')