Merge pull request #3077 from julianser/new_stacktrace_fix

theano/gof/fg.py

@@ -331,15 +331,17 @@ class FunctionGraph(utils.object2):
                             # if there is no path then r isn't really a graph input so we shouldn't be running error
                             # handler code in the first place
                             assert path is not None
-                            tr = getattr(r.tag, 'trace', None)
+                            tr = getattr(r.tag, 'trace', [])
                             detailed_err_msg = ""
-                            if tr:
-                                sio = StringIO()
-                                traceback.print_list(tr, sio)
-                                tr = sio.getvalue()
+                            if len(tr) > 0:
                                 detailed_err_msg += "\nBacktrace when the variable is created:\n"
-                                detailed_err_msg += str(tr)
 
+                                # Print separate message for each element in
+                                # the list of batcktraces
+                                sio = StringIO()
+                                for subtr in tr:
+                                    traceback.print_list(subtr, sio)
+                                    detailed_err_msg += str(sio.getvalue())
                             raise MissingInputError(
                                 'A variable that is an input to the graph was '
                                 'neither provided as an input to the function '

theano/gof/link.py

@@ -156,14 +156,16 @@ def raise_with_op(node, thunk=None, exc_info=None, storage_map=None):
             "HINT: Use another linker then the c linker to"
             " have the inputs shapes and strides printed.")
 
-    # Print node backtrace
-    tr = getattr(node.outputs[0].tag, 'trace', None)
-    if tr:
-        sio = StringIO()
-        traceback.print_list(tr, sio)
-        tr = sio.getvalue()
+    # Print node backtraces
+    tr = getattr(node.outputs[0].tag, 'trace', [])
+    if len(tr) > 0:
         detailed_err_msg += "\nBacktrace when the node is created:\n"
-        detailed_err_msg += str(tr)
+
+        # Print separate message for each element in the list of batcktraces
+        sio = StringIO()
+        for subtr in tr:
+            traceback.print_list(subtr, sio)
+            detailed_err_msg += str(sio.getvalue())
     else:
         hints.append(
             "HINT: Re-running with most Theano optimization disabled could"

theano/gof/op.py

@@ -458,14 +458,17 @@ class PureOp(object):
                 detailed_err_msg = (
                     "For compute_test_value, one input test value does not"
                     " have the requested type.\n")
-                tr = getattr(v.tag, 'trace', None)
-                if tr:
-                    sio = StringIO()
-                    traceback.print_list(tr, sio)
-                    tr = sio.getvalue()
+                tr = getattr(v.tag, 'trace', [])
+                if len(tr) > 0:
                     detailed_err_msg += (
                         " \nBacktrace when that variable is created:\n")
-                    detailed_err_msg += str(tr)
+                    # Print separate message for each element in the list 
+                    # of batcktraces
+                    sio = StringIO()
+                    for subtr in tr:
+                        traceback.print_list(subtr, sio)
+                        detailed_err_msg += str(sio.getvalue())
+
                 detailed_err_msg += (
                     "\nThe error when converting the test value to that"
                     " variable type:")

theano/gof/utils.py

@@ -94,7 +94,7 @@ def add_tag_trace(thing, user_line=1):
     # The order is from the oldest to the newest
     if len(tr) > user_line:
         tr = tr[-user_line:]
-    thing.tag.trace = tr
+    thing.tag.trace = [tr]
     return thing