<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>On Feb 2, 2011, at 4:58 PM, Óscar Fuentes wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div>Douglas Gregor <<a href="mailto:dgregor@apple.com">dgregor@apple.com</a>> writes:<br><br><blockquote type="cite"><blockquote type="cite">Why not just have clang's config.h just be entirely separate from llvm? While<br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">you may be duplicating a few things in a new configure.ac for clang it wouldn't<br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">be a whole lot and then you could just (effectively) ./configure clang as<br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">well and it'll just look for llvm on the system, otherwise just do a recursive<br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">configure?<br></blockquote></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">You know, now that you mention it.... yeah, that would probably be<br></blockquote><blockquote type="cite">better. Thanks, Eric!<br></blockquote><br>IMO it is perfectly fine to use the config.h header generated for<br>LLVM. Else we are duplicating a big chunk of code. Sharing as much<br>infrastructure with LLVM as posible reduces maintenance and ensures up<br>to some point that Clang operates the same regardless how you build it.<br><br></div></blockquote><div><br></div><div>True, however...</div><br><blockquote type="cite"><div>Apart from that, Eric, please note that we are talking about a<br>CMake-only feature. Unless you plan to change the LLVM build system (the<br>traditional one) for implementing it there is no gain at all for the<br>users on duplicating the platform tests inside the Clang tree.<br></div></blockquote></div><br><div>Conditionally including files into llvm based on build system is a non-starter</div><div>for me. It's just ridiculous.</div><div><br></div><div>That said, it looks like the config files are already installed by default when</div><div>you install llvm which should solve the needing to configure llvm problem when</div><div>building clang as a top level. There should still be a way for it to configure</div><div>itself, but that's less of an issue for the cmake side of things.</div><div><br></div><div>In addition, I'm sure there are a number of things that are configured at the top</div><div>level for llvm that aren't needed for clang and for clang that aren't needed</div><div>for llvm.</div><div><br></div><div>-eric</div></body></html>