Allow developers to disable default includes and libs paths

[kalbasit]

Due to a mismatch between the GCC we use for our project, and the new version delivered on Ubuntu 22.04, our bundle started failing. I traced the issue to GCC being called with -I/usr/include. By adding --without-default-header-paths to the gem install call make it work for us.

[keithdoggett]

@kalbasit thanks for the PR sorry I let this slip. This looks good to me and seems like a reasonable solution.

@BuonOmo what are your thoughts on this? You're definitely more familiar with extconfs and building Ruby extensions than I am so maybe you've seen a better way to handle this.

[BuonOmo]

I traced the issue to GCC being called with -I/usr/include

This generates what kind of issue ? Just want to be thorough here :)

I think that adding a specific config here is adding complexity in the build process (one more way to do it), hence we should proceed carefully and with good reasons. If the issue could be fixed upstream, it would be for the best!

[kalbasit]

I traced the issue to GCC being called with -I/usr/include

This generates what kind of issue ? Just want to be thorough here :)

I think that adding a specific config here is adding complexity in the build process (one more way to do it), hence we should proceed carefully and with good reasons. If the issue could be fixed upstream, it would be for the best!

I'm sorry it's been a while; Too many GitHub notifications 😢

Anyways, IIRC the build was failing because it was trying to use system dependencies and we needed it to use specified dependencies coming from another place, Nix in this case. Either way, it allows us to disable the system dependencies and provide explicitly where to find dependencies. I don't think that you need to test this as it does not really affect anyone except those looking to explicitly disable system dependencies for one reason or another. Looking at other gems, for example, nokogiri, they also provide similar flags.