use sin6_addr.s6_addr instead of "(u_char *) & .sin6_addr"

src/core/ngx_inet.c

diff --git a/src/core/ngx_inet.c b/src/core/ngx_inet.c
index 326383b..7dfd341 100644
--- a/src/core/ngx_inet.c
+++ b/src/core/ngx_inet.c
@@ -221,7 +221,7 @@
             text[n++] = '[';
         }
 
-        n = ngx_inet6_ntop((u_char *) &sin6->sin6_addr, &text[n], len);
+        n = ngx_inet6_ntop(sin6->sin6_addr.s6_addr, &text[n], len);
 
         if (port) {
             n = ngx_sprintf(&text[1 + n], "]:%d",
@@ -771,7 +771,7 @@
     u->host.len = len;
     u->host.data = host;
 
-    if (ngx_inet6_addr(host, len, (u_char *) &sin6->sin6_addr) != NGX_OK) {
+    if (ngx_inet6_addr(host, len, sin6->sin6_addr.s6_addr) != NGX_OK) {
         u->err = "invalid IPv6 address";
         return NGX_ERROR;
     }

src/http/ngx_http_variables.c

diff --git a/src/http/ngx_http_variables.c b/src/http/ngx_http_variables.c
index b25e648..a8f5d96 100644
--- a/src/http/ngx_http_variables.c
+++ b/src/http/ngx_http_variables.c
@@ -887,7 +887,7 @@
         v->valid = 1;
         v->no_cacheable = 0;
         v->not_found = 0;
-        v->data = (u_char *) &sin6->sin6_addr;
+        v->data = sin6->sin6_addr.s6_addr;
 
         break;
 #endif