fix r2579

src/http/ngx_http_parse.c

diff --git a/src/http/ngx_http_parse.c b/src/http/ngx_http_parse.c
index 87b6539..49f536a 100644
--- a/src/http/ngx_http_parse.c
+++ b/src/http/ngx_http_parse.c
@@ -1534,6 +1534,8 @@
 
     last = p + uri->len;
 
+    args->len = 0;
+
     while (p < last) {
 
         ch = *p++;