Merged

doc/library/config.txt

@@ -188,6 +188,16 @@ import theano and print the config variable, as in:
 
     When the mode is Mode, it sets the default optimizer used.
 
+.. attribute:: on_opt_error
+
+    String value: 'warn' or 'raise'
+
+    Default: 'warn'
+
+    When a crash occurs while trying to apply some optimization, either warn
+    the user and skip this optimization ('warn'), or raise the exception
+    ('raise').
+
 .. attribute:: config.warn.ignore_bug_before
 
     String value: 'None', 'all', '0.3'

theano/configdefaults.py

@@ -71,6 +71,10 @@ AddConfigVar('optimizer',
         "Default optimizer. If not None, will use this linker with the Mode object(not ProfileMode or DebugMode)",
         EnumStr('fast_run', 'merge', 'fast_compile', 'None'))
 
+AddConfigVar('on_opt_error',
+        "What to do when an optimization crashes: warn and skip it, or raise the exception",
+        EnumStr('warn', 'raise'))
+
 AddConfigVar('home',
         "User home directory",
         StrParam(os.getenv("HOME", os.path.expanduser('~'))))

theano/gof/opt.py

@@ -14,9 +14,10 @@ import utils
 import unify
 import toolbox
 import op
+import theano
+from theano import config
 from theano.gof.python25 import any, all
 from theano.configparser import AddConfigVar, BoolParam, config
-import theano
 
 #if sys.version_info[:2] >= (2,5):
 #  from collections import defaultdict
@@ -122,6 +123,8 @@ class SeqOptimizer(Optimizer, list):
         _logger.error("ERROR: SeqOptimizer apply %s"% str(optimizer))
         _logger.error("Traceback:")
         _logger.error(traceback.format_exc())
+        if config.on_opt_error == 'raise':
+            raise exc
 
     def __init__(self, *opts, **kw):
         """WRITEME"""
@@ -767,7 +770,7 @@ class NavigatorOptimizer(Optimizer):
         _logger.error("ERROR: Optimization failure due to: %s" % str(local_opt))
         _logger.error("TRACEBACK:")
         _logger.error(traceback.format_exc())
-        if isinstance(exc, AssertionError):
+        if isinstance(exc, AssertionError) or config.on_opt_error == 'raise':
             raise exc
     @staticmethod
     def warn_inplace(exc, nav, repl_pairs, local_opt):