allow "sendfile" in "if" context
diff --git a/src/http/ngx_http_core_module.c b/src/http/ngx_http_core_module.c
index 2bff245..9431c88 100644
--- a/src/http/ngx_http_core_module.c
+++ b/src/http/ngx_http_core_module.c
@@ -275,7 +275,8 @@
       NULL },
 
     { ngx_string("sendfile"),
-      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
+      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_HTTP_LIF_CONF
+                        |NGX_CONF_TAKE1,
       ngx_conf_set_flag_slot,
       NGX_HTTP_LOC_CONF_OFFSET,
       offsetof(ngx_http_core_loc_conf_t, sendfile),