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To quote jscipione (from 95e8362c52af35a4012ca4d0facd62fb9856b619), "Let me tell you a story about a bug" -- though this tale spans a much lesser time than that one did. In 5e19679ea35a79a26477c6215c7abba9bb7c4d00, I enabled libroot_build for Haiku, instead of using the system libroot as we had before. There were a number of bugs introduced along with this that I hadn't fixed (and there may be more after this), but most of the obvious ones (crashes on x86_64...) were fixed shortly enough. Attribute usage, though, was a different story. Unlike most of the POSIX calls in libroot, which were aliasing system functions no matter what the platform, the attribute calls were not, as they are specific to Haiku. Initially I had completely forgot about them, and it wasn't until a few days later when I noticed that I had an "attributes" directory in my generated that I realized that the "generic" attribute layer was being used on Haiku. I attempted a fix for this in 5e19679ea35a79a26477c6215c7abba9bb7c4d00, thinking that would clear the problem up, but I didn't actually run a test beyond seeing that my BuildConfig had been updated properly. In fact, BuildSetup was hard-wired to not even pass that definition through on Haiku, and so that commit had in effect caused nothing. My initial "fix" of just changing BuildSetup then caused a build failure, as while libroot_build itself compiled, it ran into errors whenever attributes were used, because in letting the real libroot's attribute calls shine through, I had bypassed libroot_build's FD emulation/shim layer. Then I tried and failed at three separate attempts to solve this with code: - a version of the "fs_attr_...h" interface for Haiku. This proved possible in theory, but in practice I would need to reimplement a lot of attribute handling code in it, because all I had access to from there was syscalls. - a version of "fs_attr_untyped" that bypassed its reimplementations of the "fs*attr" functions for the libroot ones, only using the FD shim layer. This proved possibly not even theoretically possible because it would have caused preprocessor hell in some of the build headers, and also assumptions about how attributes are read were totally different. - a completely new "fs_attr_haiku" that was a completely new interface to the fs*attr functions. This proved practically impossible because of the need to include structures from the system libroot to call out to readdir, etc. that attempts to solve would also have caused preprocessor hell. Then I realized that the Linux xattr emulation library, which I'd used as a reference when attempting the first solution, was shipped by default as a system library in all builds of Haiku ... and so I could just tell fs_attr_untyped to use the Linux xattr handler, and then link against libgnu. So that is how I arrived at this strange and decidedly unorthodox solution to a problem of my own creation.