From c6ddf92b70a2b75674eda05018ecfa3c9d11fb63 Mon Sep 17 00:00:00 2001
From: codygunton <codygunton@gmail.com>
Date: Tue, 31 Oct 2023 21:26:31 +0000
Subject: [PATCH] Handle case of no concatenations.

---
 .../cpp/src/barretenberg/honk/pcs/zeromorph/zeromorph.hpp       | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/barretenberg/cpp/src/barretenberg/honk/pcs/zeromorph/zeromorph.hpp b/barretenberg/cpp/src/barretenberg/honk/pcs/zeromorph/zeromorph.hpp
index fda7402a466..b443ded5b34 100644
--- a/barretenberg/cpp/src/barretenberg/honk/pcs/zeromorph/zeromorph.hpp
+++ b/barretenberg/cpp/src/barretenberg/honk/pcs/zeromorph/zeromorph.hpp
@@ -357,7 +357,7 @@ template <typename Curve> class ZeroMorphProver_ {
         };
 
         size_t num_groups = concatenation_groups.size();
-        size_t num_chunks_per_group = concatenation_groups[0].size();
+        size_t num_chunks_per_group = concatenation_groups.empty() ? 0 : concatenation_groups[0].size();
         // Concatenated polynomials
         // std::vector<Polynomial> concatenated_polynomials;
         Polynomial concatenated_batched(N);