diff --git a/nimble/host/src/ble_hs_hci.c b/nimble/host/src/ble_hs_hci.c
index 2d74e4b6e..e8ba0aa6d 100644
--- a/nimble/host/src/ble_hs_hci.c
+++ b/nimble/host/src/ble_hs_hci.c
@@ -108,7 +108,7 @@
 
 struct err_code {
     int error_code;
-    char *msg;
+    const char *msg;
 };
 
 static struct err_code core_err_code_list[] = {