On Fri, May 10, 2019 at 10:51:16PM +0100, Ken Moffat via blfs-dev wrote:
> On Thu, May 09, 2019 at 12:59:39AM +0100, Ken Moffat via blfs-dev wrote:
> > On Wed, May 08, 2019 at 11:53:01PM +0100, Ken Moffat wrote:
> > > 
> > > If I get time, I'll try building with gcc (8.2.0) to see if the
> > > results are better or worse.
> > > 
> > Started it off (ld.bfd, disable debug symbols, gcc) and got back to
> > it in time to watch the final link : again, that was over in the
> > blink of an eye.  And the fastest of this set of builds.  I had over
> > 7.5 GB ov available real memory, so no comment on how little I can
> > get away with for this.
> > 
> Problem: it used gcc for the initial part of the configuration, but
> then switched to clang after finding that.  Since the early part
> takes less than a minute, I have to conclude that the speed-up I
> thought was from using gcc was just random variation from the
> build-system written in Python (can you tell I hate Python
> build-systems ?).
> 
> I just noticed because I came back to my machine where I'm building
> a new system, expecting firefox would have finished, but saw it was
> still building, then looked at top and saw a lot of clang-8
> processes.  Stopped it, the log shows (and I now see similar for
> 67-beta)
> 
>  0:27.16 checking for the target C compiler... /usr/bin/clang
>  0:27.16 checking whether the target C compiler can be used... yes
> 
> Meanwhile, 67 might be a day or two late - the first candidate for
> beta19 appeared earlier this morning (my timezone), not sure if that
> beta is out yet (waiting until I've built firefox before checking!),
> but this implies the release candidates will probably not start
> getting published for a day or two.  But who knows.
> 
By using CC=gcc CXX=g++ it builds using gcc and g++ for all the C
(not much, I think) and C++ code.  The link with bfd is still fast,
although it definitely uses towards 1GB of virtual RAM, but the
build and installed files (66.0.5, gcc-9.1) are a bit bigger than
for 67.0b18, llvm-7.

I'm inclined to revert to using gcc for the C and C++ parts, because
I believe it is a more-reliable toolchain.  Unfortunately, the rust
parts are wedded to LLVM.

Will do some more builds on older systems before making a definite
decision.

ĸen
-- 
Before the universe began, there was a sound. It went: "One, two, ONE,
two, three, four" [...] The cataclysmic power chord that followed was
the creation of time and space and matter and it does Not Fade Away.
 - wiki.lspace.org/mediawiki/Music_With_Rocks_In


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