diff --git a/profile.c b/profile.c
index 855d16c86..14b76f70e 100644
--- a/profile.c
+++ b/profile.c
@@ -770,6 +770,7 @@ struct plot_info calculate_max_limits_new(struct dive *dive, struct divecomputer
 	if (minpressure > maxpressure)
 		minpressure = 0;
 
+	memset(&pi, 0, sizeof(pi));
 	pi.maxdepth = maxdepth;
 	pi.maxtime = maxtime;
 	pi.maxpressure = maxpressure;