--- src/http/ngx_http_upstream.c.orig	2018-03-20 10:58:32.000000000 -0500
+++ src/http/ngx_http_upstream.c	2018-03-21 16:33:11.000000000 -0500
@@ -164,8 +164,6 @@
     ngx_http_variable_value_t *v, uintptr_t data);
 static ngx_int_t ngx_http_upstream_response_length_variable(
     ngx_http_request_t *r, ngx_http_variable_value_t *v, uintptr_t data);
-static ngx_int_t ngx_http_upstream_header_variable(ngx_http_request_t *r,
-    ngx_http_variable_value_t *v, uintptr_t data);
 static ngx_int_t ngx_http_upstream_trailer_variable(ngx_http_request_t *r,
     ngx_http_variable_value_t *v, uintptr_t data);
 static ngx_int_t ngx_http_upstream_cookie_variable(ngx_http_request_t *r,
@@ -5466,7 +5464,7 @@
 }
 
 
-static ngx_int_t
+ngx_int_t
 ngx_http_upstream_header_variable(ngx_http_request_t *r,
     ngx_http_variable_value_t *v, uintptr_t data)
 {