id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	uname	nginx_version
1285	map regexp positional captures interfere with location regexp positional captures	dimaslv@…		"I have map configuration like this:
    map $uri $rewrite_scheme {
        default              ""http"";
        ~*test ""https"";
    }

And location configuration like this:
        location ~ ^/__proxy_host/(host1|host2)/(.*)$ {
            proxy_pass $rewrite_scheme://$1/$2$is_args$args;
        }

Before I have added map configuration location was working as expected, but after adding map all positional captures inside location became empty. Probably it is due to map initialization on variable call (which occurs after location).
If it is by design, then it would be nice to document this behavior as it is too hard to investigate.

As a solution named captures could be used like this:
        location ~ ^/__proxy_host/(?<rewrite_host>host1|host2)/(?<rewrite_path>.*)$ {
            proxy_pass $rewrite_scheme://$rewrite_host/$rewrite_path$is_args$args;
        }"	defect	new	minor		documentation	1.10.x		map location		Linux srv 3.10.0-327.36.3.el7.x86_64 #1 SMP Mon Oct 24 16:09:20 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux	"nginx version: nginx/1.10.3
built by gcc 4.8.5 20150623 (Red Hat 4.8.5-4) (GCC) 
built with OpenSSL 1.1.0c  10 Nov 2016
TLS SNI support enabled
configure arguments: --prefix=/etc/nginx --sbin-path=/usr/sbin/nginx --modules-path=/usr/lib64/nginx/modules --conf-path=/etc/nginx/nginx.conf --error-log-path=/var/log/nginx/error.log --http-log-path=/var/log/nginx/access.log --pid-path=/var/run/nginx.pid --lock-path=/var/run/nginx.lock --http-client-body-temp-path=/var/cache/nginx/client_temp --http-proxy-temp-path=/var/cache/nginx/proxy_temp --http-fastcgi-temp-path=/var/cache/nginx/fastcgi_temp --http-uwsgi-temp-path=/var/cache/nginx/uwsgi_temp --http-scgi-temp-path=/var/cache/nginx/scgi_temp --user=nginx --group=nginx --with-file-aio --with-threads --with-ipv6 --with-http_addition_module --with-http_auth_request_module --with-http_dav_module --with-http_flv_module --with-http_gunzip_module --with-http_gzip_static_module --with-http_mp4_module --with-http_random_index_module --with-http_realip_module --with-http_secure_link_module --with-http_slice_module --with-http_ssl_module --with-http_stub_status_module --with-http_sub_module --with-http_v2_module --with-stream --with-stream_ssl_module --add-module=/opt/nginx-sla --with-cc-opt='-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -m64 -mtune=generic -I /opt/openssl110/include' --with-ld-opt='-L /opt/openssl110/lib'"