fix coercion optimisation

diff --git a/Cython/Compiler/Optimize.py b/Cython/Compiler/Optimize.py
index cb2666e98ae70b49549416a3162732dc98467bcf..c9b24851f52ee16439faeadea2f9bfbd5873acbc 100644 (file)
--- a/Cython/Compiler/Optimize.py
+++ b/Cython/Compiler/Optimize.py
@@ -1044,6 +1044,8 @@ class OptimizeBuiltinCalls(Visitor.EnvTransform):
         """
         self.visitchildren(node)
         arg = node.arg
+        if isinstance(arg, ExprNodes.PyTypeTestNode):
+            arg = arg.arg
         if isinstance(arg, ExprNodes.CoerceToPyTypeNode):
             if arg.type in (PyrexTypes.py_object_type, Builtin.bool_type):
                 return arg.arg.coerce_to_boolean(self.current_env())