diff --git a/image_analysis/geom_refinement/XtalOptimizer.cpp b/image_analysis/geom_refinement/XtalOptimizer.cpp
index aec455c9..0366b0ca 100644
--- a/image_analysis/geom_refinement/XtalOptimizer.cpp
+++ b/image_analysis/geom_refinement/XtalOptimizer.cpp
@@ -495,7 +495,9 @@ bool XtalOptimizerInternal(XtalOptimizerData &data,
 
         ceres::Problem problem;
 
-        double latt_vec0[3], latt_vec1[3], latt_vec2[3];
+double latt_vec0[3] = {0.0, 0.0, 0.0};
+double latt_vec1[3] = {0.0, 0.0, 0.0};
+double latt_vec2[3] = {0.0, 0.0, 0.0};
 
         double rot_vec[3] = {1, 0, 0};