diff --git a/loopy/codegen/bounds.py b/loopy/codegen/bounds.py
index 7b90feb08b46c6c0103d241bb308d6f40f405417..c9e79f6bcc17f3ed3166dfc18cc012721410af6c 100644
--- a/loopy/codegen/bounds.py
+++ b/loopy/codegen/bounds.py
@@ -25,6 +25,7 @@ THE SOFTWARE.
 
 import islpy as isl
 from islpy import dim_type
+from pymbolic.mapper.stringifier import PREC_NONE
 
 
 def constraint_to_code(ccm, cns):
@@ -34,7 +35,7 @@ def constraint_to_code(ccm, cns):
         comp_op = ">="
 
     from loopy.symbolic import constraint_to_expr
-    return "%s %s 0" % (ccm(constraint_to_expr(cns), 'i'), comp_op)
+    return "%s %s 0" % (ccm(constraint_to_expr(cns), PREC_NONE, "i"), comp_op)
 
 
 # {{{ bounds check generator
diff --git a/loopy/codegen/instruction.py b/loopy/codegen/instruction.py
index f6b103210ac9f5dcf0f615a8e3d9432ad51082fd..6ce16944230f42a25f4beecc21351e002ca21d53 100644
--- a/loopy/codegen/instruction.py
+++ b/loopy/codegen/instruction.py
@@ -1,7 +1,6 @@
 """Code generation for Instruction objects."""
-from __future__ import division
-from __future__ import absolute_import
-from six.moves import range
+
+from __future__ import division, absolute_import
 
 __copyright__ = "Copyright (C) 2012 Andreas Kloeckner"
 
@@ -26,8 +25,10 @@ THE SOFTWARE.
 """
 
 
+from six.moves import range
 import islpy as isl
 from loopy.codegen import GeneratedInstruction
+from pymbolic.mapper.stringifier import PREC_NONE
 
 
 def wrap_in_conditionals(codegen_state, domain, check_inames, required_preds, stmt):
@@ -92,7 +93,6 @@ def generate_expr_instruction_code(kernel, insn, codegen_state):
     (assignee_var_name, assignee_indices), = insn.assignees_and_indices()
     target_dtype = kernel.get_var_descriptor(assignee_var_name).dtype
 
-    from pymbolic.mapper.stringifier import PREC_NONE
     from cgen import Assign
     from loopy.codegen.expression import dtype_to_type_context
     lhs_code = ccm(insn.assignee, prec=PREC_NONE, type_context=None)
@@ -123,7 +123,7 @@ def generate_expr_instruction_code(kernel, insn, codegen_state):
         if assignee_indices:
             printf_format += "[%s]" % ",".join(len(assignee_indices) * ["%d"])
             printf_args.extend(
-                    ccm(i, prec=None, type_context="i")
+                    ccm(i, prec=PREC_NONE, type_context="i")
                     for i in assignee_indices)
 
         if kernel.options.trace_assignment_values:
@@ -186,5 +186,4 @@ def generate_c_instruction_code(kernel, insn, codegen_state):
     return Block(body)
 
 
-
 # vim: foldmethod=marker
diff --git a/loopy/codegen/loop.py b/loopy/codegen/loop.py
index 70e52eb37d277aee457963e013aee793f8b86db4..f5e9c9f7fc87e24b47e193e6740a928f695cd3e2 100644
--- a/loopy/codegen/loop.py
+++ b/loopy/codegen/loop.py
@@ -29,6 +29,7 @@ from loopy.codegen import gen_code_block
 import islpy as isl
 from islpy import dim_type
 from loopy.codegen.control import build_loop_nest
+from pymbolic.mapper.stringifier import PREC_NONE
 
 
 # {{{ conditional-reducing slab decomposition
@@ -361,7 +362,7 @@ def generate_sequential_loop_dim_code(kernel, sched_index, codegen_state):
             # single-trip, generate just a variable assignment, not a loop
             result.append(gen_code_block([
                 Initializer(Const(POD(kernel.index_dtype, loop_iname)),
-                    ccm(aff_to_expr(static_lbound), "i")),
+                    ccm(aff_to_expr(static_lbound), PREC_NONE, "i")),
                 Line(),
                 inner,
                 ]))
@@ -373,8 +374,9 @@ def generate_sequential_loop_dim_code(kernel, sched_index, codegen_state):
             result.append(wrap_in(For,
                     "%s %s = %s"
                     % (dtype_to_ctype(kernel.index_dtype),
-                        loop_iname, ccm(aff_to_expr(static_lbound), "i")),
-                    "%s <= %s" % (loop_iname, ccm(aff_to_expr(static_ubound), "i")),
+                        loop_iname, ccm(aff_to_expr(static_lbound), PREC_NONE, "i")),
+                    "%s <= %s" % (
+                        loop_iname, ccm(aff_to_expr(static_ubound), PREC_NONE, "i")),
                     "++%s" % loop_iname,
                     inner))