id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	uname	nginx_version
1404	try_files not working after if condition	x2x4com@…		"location ~ ^/u(/.*) {
        set $router $1;
        set $xargs ""&and=more"";
        #if ($args) {
        #   set $noting """";
        #}
        try_files $uri /do?r=$router$xargs;
}

works fine, but if change config to 

location ~ ^/u(/.*) {
        set $router $1;
        set $xargs ""&and=more"";
        if ($args) {
           set $noting """";
        }
        try_files $uri /do?r=$router$xargs;
}

always return 404, check log

2017/10/26 11:30:06 [error] 27958#27958: *53301 open() ""/data/www/site_default/u/aaa"" failed (2: No such file or directory), client: 101.81.121.148, server: 9chain.kmdns.net, request: ""GET /u/aaa?a=1 HTTP/1.1"", host: ""ol.dev.bidpoc.com:8000""
2017/10/26 11:30:21 [notice] 27990#27990: signal process started
2017/10/26 11:30:24 [error] 27999#27999: *53304 open() ""/data/www/site_default/u/aaa"" failed (2: No such file or directory), client: 101.81.121.148, server: 9chain.kmdns.net, request: ""GET /u/aaa?a=1 HTTP/1.1"", host: ""ol.dev.bidpoc.com:8000"""	defect	closed	minor		other	1.13.x	duplicate		5.4.0 20160609	Linux Global-Proxy 4.4.0-97-generic #120-Ubuntu SMP Tue Sep 19 17:28:18 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux	"nginx version: nginx/1.13.2
built by gcc 5.4.0 20160609 (Ubuntu 5.4.0-6ubuntu1~16.04.4)
built with OpenSSL 1.0.2g  1 Mar 2016
TLS SNI support enabled
configure arguments: --prefix=/usr/local/nginx --with-debug --with-pcre-jit --with-http_ssl_module --with-http_stub_status_module --with-http_realip_module --with-http_auth_request_module --with-http_addition_module --with-http_dav_module --with-http_geoip_module --with-http_gunzip_module --with-http_gzip_static_module --with-http_image_filter_module --with-http_v2_module --with-http_sub_module --with-http_xslt_module --with-stream --with-stream_ssl_module --with-threads"