From 194a34cfa082328ecf0b37113988f820837d5b6b Mon Sep 17 00:00:00 2001
From: zac-williamson <blorktronics@gmail.com>
Date: Thu, 6 Jun 2024 10:06:40 +0000
Subject: [PATCH] fix issue `create_new_range_constraint` has an off-by-one
 error if number of bits being constrained is small (affects Noir) #6929

---
 .../stdlib_circuit_builders/ultra_circuit_builder.hpp           | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/barretenberg/cpp/src/barretenberg/stdlib_circuit_builders/ultra_circuit_builder.hpp b/barretenberg/cpp/src/barretenberg/stdlib_circuit_builders/ultra_circuit_builder.hpp
index 286ce0b165b7..10317b7a0090 100644
--- a/barretenberg/cpp/src/barretenberg/stdlib_circuit_builders/ultra_circuit_builder.hpp
+++ b/barretenberg/cpp/src/barretenberg/stdlib_circuit_builders/ultra_circuit_builder.hpp
@@ -470,7 +470,7 @@ class UltraCircuitBuilder_ : public CircuitBuilderBase<typename Arithmetization_
                 .q_o = 0,
                 .q_c = 0,
             });
-            create_new_range_constraint(variable_index, 1ULL << num_bits, msg);
+            create_new_range_constraint(variable_index, (1ULL << num_bits) - 1, msg);
         } else {
             decompose_into_default_range(variable_index, num_bits, DEFAULT_PLOOKUP_RANGE_BITNUM, msg);
         }