On Sat, Apr 6, 2019 at 1:09 AM Martin Sebor <mse...@gmail.com> wrote: > > On 4/5/19 4:02 PM, Jeff Law wrote: > > On 4/5/19 3:37 PM, Martin Sebor wrote: > >> On 4/5/19 3:29 PM, Jeff Law wrote: > >>> On 4/5/19 2:50 PM, Eric Botcazou wrote: > >>>>> Say if the first bootstrap succeeds and I then change a single > >>>>> GCC .c file and rerun make bootstrap, am I guaranteed to see > >>>>> the same fallout of the change as I would if I did a pristine > >>>>> build in a clean directory? > >>>> > >>>> No, this would imply deleting the stage2 and stage3 compilers and > >>>> that isn't > >>>> what happens. Instead the compiler of each stage is updated in > >>>> isolation. > >>>> > >>> RIght. Thus I always blow away stage2-* stage3-*, and stage1 target > >>> directories along with the "compare" stamp file. > >> > >> Thanks (all of you). It's amazing that I have been getting away > >> with it for all these years. > > I got away without removing the "compare" stamp file for a long time, > > then broke the trunk with a comparison failure :( > > > >> > >> Why is this not done automatically? I mean, what is the use case > >> for make bootstrap without doing these steps first? > > During development folks often want to rebuild without going through a > > full bootstrap. Obviously for testing the final version of a patch the > > "quick" approach of just rebuilding without blowing away the stage > > directories isn't sufficient. > > I see. So after a bootstrap and a subsequent change to a .c file, > at each stage the next bootstrap recompiles just the changed file > and relinks gcc. It doesn't actually recompile all source files > in stage 2 or 3 with the changed compiler from the last stage. > That's why it's so much faster! Make check then correctly reflects > the change but the compiler doesn't get as fully exercised because > the test suite has low coverage. > > > This is actually one of the things I'd really like to just automate. > > You point to a git commit in a public repo, the tester picks it up and > > does a bootstrap & regression test from scratch on whatever targets you > > ask for. > > That would be great to validate the final patch. > > So to be clear: the safe and also most efficient to "rebootstrap" > GCC is to remove what exactly?
Just remove everything? Toplevel configure and stage1 build is fast anyway. That's what I'm doing since forever. Richard. > (I don't see any stage2 or stage3 > directories in my build tree.) Is there a make target for this? > > Thanks > Martin
