On Mon, Feb 9, 2015 at 8:01 PM, frank ernest <doark@mail.com> wrote:<br>
<blockquote type="cite"><div class="plaintext" style="white-space: pre-wrap;">NO, this is NOT a complaint!
I'm asking why it takes 3.5 to 4.5 hours to compile.</div></blockquote><br><div>Yeah that's normal. A couple tips:</div><div><br></div><div>* -O0 actually makes it take slightly longer to compile on my machine (no, I don't understand why) but the difference is not significant. You might as well use -O2.</div><div>* Make sure you are not including any debug info if you want things to go fast. -g should not be present in CXXFLAGS. If you're currently using -g, then removing it will speed things up dramatically.</div><div>* Switching from ld.bfd to ld.gold will speed things up dramatically if you're doing a debug build (with -g). I don't remember how much faster it is for non-debug builds, but I would guess the difference is significant.</div><div>* Switching from GCC 4.8 to Clang 3.4 made non-debug builds go ~15% faster for me. This probably depends a lot on the specific compiler version, though. Upgrading from Fedora 20 (with GCC 4.8) to Fedora 21 (GCC 4.9) caused my build time to increase by >20%, which was sad.</div>