diff --git a/src/symbol.c b/src/symbol.c
index 62057ab7..816e72bc 100644
--- a/src/symbol.c
+++ b/src/symbol.c
@@ -21,6 +21,8 @@ pic_intern_cstr(pic_state *pic, const char *str)
     return e->val;
   }
 
+  str = pic_strdup(pic, str);
+
   if (pic->slen >= pic->scapa) {
 
 #if DEBUG
@@ -31,7 +33,7 @@ pic_intern_cstr(pic_state *pic, const char *str)
     pic->sym_pool = pic_realloc(pic, pic->sym_pool, sizeof(const char *) * pic->scapa);
   }
   id = pic->slen++;
-  pic->sym_pool[id] = pic_strdup(pic, str);
+  pic->sym_pool[id] = str;
   xh_put(pic->sym_tbl, str, id);
   return id;
 }