Apparently this was missing.

theano/gpuarray/type.py

@@ -387,6 +387,7 @@ class GpuArrayType(Type):
                 'float16': (float, 'npy_float16', 'NPY_FLOAT16'),
                 'float32': (float, 'npy_float32', 'NPY_FLOAT32'),
                 'float64': (float, 'npy_float64', 'NPY_FLOAT64'),
+                'bool': (int, 'npy_bool', 'NPY_BOOL'),
                 'uint8': (int, 'npy_uint8', 'NPY_UINT8'),
                 'int8': (int, 'npy_int8', 'NPY_INT8'),
                 'uint16': (int, 'npy_uint16', 'NPY_UINT16'),