xilanglangdeMacBook-Pro:pcre xinshaofeng$ brew link pcre

Linking /usr/local/Cellar/pcre/8.40... 

Error: Could not symlink bin/pcre-config

Target /usr/local/bin/pcre-config

is a symlink belonging to pcre. You can unlink it:

  brew unlink pcre

To force the link and overwrite all conflicting files:

  brew link --overwrite pcre

To list all files that would be deleted:

  brew link --overwrite --dry-run pcre

xilanglangdeMacBook-Pro:pcre xinshaofeng$ brew link --overwrite pcre

Linking /usr/local/Cellar/pcre/8.40... 261 symlinks created

xilanglangdeMacBook-Pro:pcre xinshaofeng$ brew link openresty-openssl

Linking /usr/local/Cellar/openresty-openssl/1.0.2k... 89 symlinks created

xilanglangdeMacBook-Pro:pcre xinshaofeng$ brew install homebrew/nginx/openresty

Error: You must `brew link pcre openresty-openssl` before homebrew/nginx/openresty can be installed