diff --git a/src/core/ngx_hash.c b/src/core/ngx_hash.c
index d9c157c1d..8215c2717 100644
--- a/src/core/ngx_hash.c
+++ b/src/core/ngx_hash.c
@@ -274,6 +274,10 @@ ngx_hash_init(ngx_hash_init_t *hinit, ngx_hash_key_t *names, ngx_uint_t nelts)
     }
 
     for (n = 0; n < nelts; n++) {
+        if (names[n].key.data == NULL) {
+            continue;
+        }
+
         if (hinit->bucket_size < NGX_HASH_ELT_SIZE(&names[n]) + sizeof(void *))
         {
             ngx_log_error(NGX_LOG_EMERG, hinit->pool->log, 0,