On 2017.01.25 at 09:51 -0800, Oleg Smolsky wrote: > On 2017-01-25 01:22, Jonathan Wakely wrote: > > On 25 January 2017 at 01:45, Oleg Smolsky wrote: > > > I've just noticed that gcc5.4 is 3x faster on large/complex files when it is > > > built with --enable-bootstrap (as opposed to --disable-bootstrap). I thought > > > that the stage2 compiler is already built with itself and so there should be > > > no difference between stage2 and stage3 compilers... (the host's compiler is > > > gcc 4.8) > > > > > > Do you know what's going on? > > Are you sure --enable-bootstrap is the only difference, and one isn't > > build with --enable-checking? > > > > Are both built from the exact 5.4.0 release, not a snapshot? > Hey Jonathan, yes, I'm building the official gcc 5.4.0 release this way: > > rm -rf _obj; mkdir _obj; pushd _obj > CFLAGS="-I$glibc_path/include" CXXFLAGS="-I$glibc_path/include" If you use these CXXFLAGS with --disable-bootstrap you disable all optimizations. So just add "-O2 -g" to your CXXFLAGS and you will get comparable results. -- Markus
