<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><br class=""><div><blockquote type="cite" class=""><div class="">On Dec 13, 2016, at 11:06 AM, David Chisnall <<a href="mailto:David.Chisnall@cl.cam.ac.uk" class="">David.Chisnall@cl.cam.ac.uk</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="">On 13 Dec 2016, at 19:02, Mehdi Amini via llvm-dev <<a href="mailto:llvm-dev@lists.llvm.org" class="">llvm-dev@lists.llvm.org</a>> wrote:<br class=""><blockquote type="cite" class=""><br class="">I’m totally willing to believe you that it is not possible to write the fastest ELF linker on earth (or in the universe) with a library based and reusable components approach. But clang is not the fastest C/C++ compiler available, and LLVM is not the fastest compiler framework either!<br class=""></blockquote><br class="">I’m not how it compares now, but at least when I started contributing and for a year or two after the speed of clang (especially at O0, for fast compile-test-debug cycles) was one of its big selling points.<br class=""></div></div></blockquote><div><br class=""></div></div>Some data: <div class="">- <a href="http://baptiste-wicht.com/posts/2016/11/zapcc-a-faster-cpp-compiler.html" class="">http://baptiste-wicht.com/posts/2016/11/zapcc-a-faster-cpp-compiler.html</a></div><div class="">- <a href="http://hubicka.blogspot.nl/2016/03/building-libreoffice-with-gcc-6-and-lto.html" class="">http://hubicka.blogspot.nl/2016/03/building-libreoffice-with-gcc-6-and-lto.html</a></div><div class=""><br class=""></div><div class="">That does not mean we’re not taking compile time seriously: we are and we (at least a few people I know of) are planning on improving it, hopefully significantly. I don’t believe we’d ever go against the design principles (modularity, etc.) though.</div><div class=""><br class=""></div><div class="">Also, the above data is just about clang as a C/C++ compiler. LLVM is a different beast and its overhead (that is somehow inherent with the features provided) is "well known” (for example I believe this drove: <a href="https://webkit.org/blog/5852/introducing-the-b3-jit-compiler/" class="">https://webkit.org/blog/5852/introducing-the-b3-jit-compiler/</a> ; but you can find other examples).</div><div class=""><br class=""></div><div class="">— </div><div class="">Mehdi</div><div class=""><br class=""></div></body></html>