diff --git a/runtime/caml/startup_aux.h b/runtime/caml/startup_aux.h
index 6739a2bee164..c4c89ff7af17 100644
--- a/runtime/caml/startup_aux.h
+++ b/runtime/caml/startup_aux.h
@@ -27,10 +27,12 @@ extern uintnat caml_init_max_stack_wsz;
 extern uintnat caml_trace_level;
 extern int caml_cleanup_on_exit;
 
+/* Returns 0 if the runtime is already initialized. */
+extern int caml_startup_needed();
+
 /* Common entry point to caml_startup.
-   Returns 0 if the runtime is already initialized.
    If [pooling] is 1, [caml_stat_*] functions will be backed by a pool. */
-extern int caml_startup_aux (int pooling);
+extern void caml_startup_aux (int pooling);
 
 #endif /* CAML_INTERNALS */
 
diff --git a/runtime/startup_aux.c b/runtime/startup_aux.c
index c120ea3c79ad..1bcdd1ead736 100644
--- a/runtime/startup_aux.c
+++ b/runtime/startup_aux.c
@@ -150,18 +150,32 @@ static int startup_count = 0;
 /* Has the runtime been shut down already? */
 static int shutdown_happened = 0;
 
-int caml_startup_aux(int pooling)
+int caml_startup_needed()
 {
   if (shutdown_happened == 1)
     caml_fatal_error("caml_startup was called after the runtime "
                      "was shut down with caml_shutdown");
 
-  /* Second and subsequent calls are ignored,
+  /* Second and subsequent startups are ignored,
      since the runtime has already started */
   startup_count++;
-  if (startup_count > 1)
-    return 0;
+  return (startup_count == 1);
+}
+
+
+int caml_shutdown_needed()
+{
+  if (startup_count <= 0)
+    caml_fatal_error("a call to caml_shutdown has no "
+                     "corresponding call to caml_startup");
 
+  /* Do nothing unless it's the last call remaining */
+  startup_count--;
+  return (startup_count == 0);
+}
+
+void caml_startup_aux(int pooling)
+{
   /* Determine options */
 #ifdef DEBUG
   caml_verb_gc = 0x3F;
@@ -196,8 +210,6 @@ int caml_startup_aux(int pooling)
   caml_init_backtrace();
   caml_record_backtrace(Val_int(record_backtrace));
   init_atom_table();
-
-  return 1;
 }
 
 static void call_registered_value(char* name)
@@ -209,13 +221,7 @@ static void call_registered_value(char* name)
 
 CAMLexport void caml_shutdown(void)
 {
-  if (startup_count <= 0)
-    caml_fatal_error("a call to caml_shutdown has no "
-                     "corresponding call to caml_startup");
-
-  /* Do nothing unless it's the last call remaining */
-  startup_count--;
-  if (startup_count > 0)
+  if (!caml_shutdown_needed())
     return;
 
   call_registered_value("Pervasives.do_at_exit");
diff --git a/runtime/startup_byt.c b/runtime/startup_byt.c
index 4ea771a4bd47..f66b43b35ee2 100644
--- a/runtime/startup_byt.c
+++ b/runtime/startup_byt.c
@@ -459,11 +459,12 @@ CAMLexport void caml_main(char_os **argv)
   char_os * shared_lib_path, * shared_libs;
   char_os * exe_name, * proc_self_exe;
 
-  if (!caml_startup_aux(0)) {
-    /* startup was already done once */
-    return;
+  if (!caml_startup_needed()) {
+      return;
   }
 
+  caml_startup_aux(0);
+
   caml_ext_table_init(&caml_shared_libs_path, 8);
 
   /* Determine position of bytecode file */
@@ -582,11 +583,12 @@ CAMLexport value caml_startup_code_exn(
   char_os * cds_file;
   char_os * exe_name;
 
-  if (!caml_startup_aux(pooling)) {
-    /* startup was already done once */
+  if (!caml_startup_needed()) {
     return Val_unit;
   }
 
+  caml_startup_aux(pooling);
+
   cds_file = caml_secure_getenv(T("CAML_DEBUG_FILE"));
   if (cds_file != NULL) {
     caml_cds_file = caml_stat_strdup_os(cds_file);
diff --git a/runtime/startup_nat.c b/runtime/startup_nat.c
index ed15f88662b9..13672f057f93 100644
--- a/runtime/startup_nat.c
+++ b/runtime/startup_nat.c
@@ -103,11 +103,12 @@ value caml_startup_common(char_os **argv, int pooling)
   char_os * exe_name, * proc_self_exe;
   char tos;
 
-  if (!caml_startup_aux(pooling)) {
-    /* startup was already done once */
+  if (!caml_startup_needed()) {
     return Val_unit;
   }
 
+  caml_startup_aux(pooling);
+
   caml_init_frame_descriptors();
   Caml_state->top_of_stack = &tos;
   init_static();