diff --git a/cpp/src/branch_and_bound/branch_and_bound.hpp b/cpp/src/branch_and_bound/branch_and_bound.hpp
index 1be148cdcb..b91e83f240 100644
--- a/cpp/src/branch_and_bound/branch_and_bound.hpp
+++ b/cpp/src/branch_and_bound/branch_and_bound.hpp
@@ -288,7 +288,7 @@ class branch_and_bound_t {
   // In case, a best-first thread encounters a numerical issue when solving a node,
   // its blocks the progression of the lower bound as it cannot explore the
   // corresponding subtree.
-  omp_atomic_t<f_t> lower_bound_numerical_;
+  omp_atomic_t<f_t> lower_bound_numerical_{std::numeric_limits<f_t>::infinity()};
   std::function<void(f_t)> user_bound_callback_;
 
   void print_table_header();