Before compiling and installing nginx, you need to install pcre. When pcre-8.37 is compiled and installed, a warning message appears:

libtool: warning: relinking 'libpcreposix.la'
...
...
libtool: warning: relinking 'libpcrecpp.la'

What's wrong with this warning message? Does it matter?

In addition: pcre has two versions, the latest ones are pcre-8.37 and pcre2-10.20. Although a warning message appears during installation of pcre-8.37, nginx can be installed successfully. If you install pcre2-10.20, the installation of nginx will fail. Why?