diff --git a/ctdb/include/ctdb_private.h b/ctdb/include/ctdb_private.h
index 88f775ce126..b36eaa08a08 100644
--- a/ctdb/include/ctdb_private.h
+++ b/ctdb/include/ctdb_private.h
@@ -609,9 +609,11 @@ int switch_from_server_to_client(struct ctdb_context *ctdb);
 void ctdb_track_child(struct ctdb_context *ctdb, pid_t pid);
 
 pid_t ctdb_fork(struct ctdb_context *ctdb);
-pid_t ctdb_vfork_exec(TALLOC_CTX *mem_ctx, struct ctdb_context *ctdb,
-		      const char *helper, int helper_argc,
-		      const char **helper_argv);
+pid_t ctdb_vfork_exec(TALLOC_CTX *mem_ctx,
+		      struct ctdb_context *ctdb,
+		      const char *helper,
+		      int helper_argc,
+		      const char *const *helper_argv);
 
 struct tevent_signal *ctdb_init_sigchld(struct ctdb_context *ctdb);
 
diff --git a/ctdb/server/ctdb_fork.c b/ctdb/server/ctdb_fork.c
index 1065423199d..8f3e0896b32 100644
--- a/ctdb/server/ctdb_fork.c
+++ b/ctdb/server/ctdb_fork.c
@@ -105,9 +105,11 @@ pid_t ctdb_fork(struct ctdb_context *ctdb)
 /*
  * vfork + exec
  */
-pid_t ctdb_vfork_exec(TALLOC_CTX *mem_ctx, struct ctdb_context *ctdb,
-		      const char *helper, int helper_argc,
-		      const char **helper_argv)
+pid_t ctdb_vfork_exec(TALLOC_CTX *mem_ctx,
+		      struct ctdb_context *ctdb,
+		      const char *helper,
+		      int helper_argc,
+		      const char *const *helper_argv)
 {
 	pid_t pid;
 	struct timeval before;