diff --git a/internal/imemo.h b/internal/imemo.h
index eee3dd7185..3b91ef4b81 100644
--- a/internal/imemo.h
+++ b/internal/imemo.h
@@ -131,6 +131,7 @@ struct MEMO {
 #ifndef RUBY_RUBYPARSER_H
 typedef struct rb_imemo_tmpbuf_struct rb_imemo_tmpbuf_t;
 #endif
+VALUE rb_imemo_new(enum imemo_type type, VALUE v0, size_t size);
 VALUE rb_imemo_tmpbuf_new(void);
 struct vm_ifunc *rb_vm_ifunc_new(rb_block_call_func_t func, const void *data, int min_argc, int max_argc);
 static inline enum imemo_type imemo_type(VALUE imemo);
@@ -147,7 +148,6 @@ void rb_imemo_mark_and_move(VALUE obj, bool reference_updating);
 void rb_imemo_free(VALUE obj);
 
 RUBY_SYMBOL_EXPORT_BEGIN
-VALUE rb_imemo_new(enum imemo_type type, VALUE v0, size_t size);
 const char *rb_imemo_name(enum imemo_type type);
 RUBY_SYMBOL_EXPORT_END