[arch-general] Build configuration settings for samba

[Newbugreport]

My Arch server hit https://bugzilla.samba.org/show_bug.cgi?id=10541 in a bad way, blocking all SMB writes from my Ubuntu 17.10 client. Since the bug is unfixed, I'd like to make a custom build of smbd to get things working. My test builds of samba don't appear to match how samba is built in Arch.

Where can I find documentation on how samba is build in Arch, especially configuration details?