Attempting to build packaged libsqlite unexpectedly links against system libraries

I have run into an issue installing this gem with the compiled native extension. When I run a build, if there are any sqlite3 headers and libraries installed on my system, the sqlite3_native.so library ends up being dynamically linked against that system library. This is the case even though I am not setting --enable-system-libraries or even if I set --disable-system-libraries explicitly. If I uninstall the library from the system, then the gem extension does link statically against the packaged libsqlite3 the way I expect.

Originally, I ran into this issue on Rocky Linux 9 with Ruby 3.0, sqlite3-ruby 2.0.4. Ancient ruby/rubygems mean that it can't use the precompiled gems, but I really needed the newer packaged version of libsqlite3. I have since been able to reproduce this issue with the latest version of sqlite3-ruby and ruby 3.3.7.

In my mind, this is unexpected behavior, since the gem is going to the trouble of building sqlite3, and since the default is --disable-system-libraries. For my own purposes I've hacked the extconf.rb to static link against the packaged libsqlite3 by default. I'm not an expert with ruby extension building or this gem; If this would be useful for the project, please let me know and I can open a pull request. Also willing to rework it if there is a better approach that anyone is aware of. benjunmun/sqlite3-ruby/tree/fix-packaged-extension-build@31abd7c

Start in extconf.rb and inspect how --enable-system-libraries and --disable-system-libraries affect the native extension build. Reproduce the build with system SQLite headers and libraries installed, then compare the linkage of sqlite3_native.so with the packaged libsqlite3 path. Done means the packaged build links statically against its bundled SQLite library when system libraries are disabled.