diff --git a/doc/tutorial.rst b/doc/tutorial.rst
index 35fcd64f8..f6c8448f0 100644
--- a/doc/tutorial.rst
+++ b/doc/tutorial.rst
@@ -1919,7 +1919,7 @@ Now to make things more interesting, we'll create a kernel with barriers:
           barrier(CLK_LOCAL_MEM_FENCE) /* for c (insn rev-depends on insn_0) */;
           c[990 * i + 99 * j + lid(0) + 1] = 2 * a[980 * i + 98 * j + lid(0) + 1];
           barrier(CLK_LOCAL_MEM_FENCE) /* for c (insn_0 depends on insn) */;
-          e[980 * i + 98 * j + lid(0) + 1] = c[990 * i + 99 * j + 1 + lid(0) + 1] + c[990 * i + 99 * j + -1 + lid(0) + 1];
+          e[980 * i + 98 * j + lid(0) + 1] = c[1 + 990 * i + 99 * j + lid(0) + 1] + c[-1 + 990 * i + 99 * j + lid(0) + 1];
         }
     }
 
diff --git a/loopy/target/c/codegen/expression.py b/loopy/target/c/codegen/expression.py
index d1a75ea6e..1d7d5d2fd 100644
--- a/loopy/target/c/codegen/expression.py
+++ b/loopy/target/c/codegen/expression.py
@@ -52,6 +52,7 @@
     LocalHardwareAxisIndex,
     ResolvedFunction,
     SubArrayRef,
+    flatten,
 )
 from loopy.target.c import CExpression
 from loopy.type_inference import TypeInferenceMapper, TypeReader
@@ -336,8 +337,8 @@ def make_var(name):
                 result = self.make_subscript(
                         ary,
                         make_var(access_info.array_name),
-                        simplify_using_aff(
-                            self.kernel, self.rec_arith(subscript, "i")))
+                        flatten(self.rec_arith(
+                            simplify_using_aff(self.kernel, subscript), "i")))
 
             if access_info.vector_index is not None:
                 return self.codegen_state.ast_builder.add_vector_access(