GCC Bootstrap FreeBSD 11.0

[Bill Sorenson]

I just want to report on my experience bootstrapping GCC 6.2.0 on a Sunfire
V245 running 11.0

I was unable to do a direct full bootstrap with the system compiler which I
sort of expected. What I had to do was build gcc47 from ports (not doing a
full bootstrap) and then build gcc6 with that, again not a full bootstrap.
Finally I rebuilt gcc6 with itself again.

Any time I did a full bootstrap I got stage 2 to 3 comparison errors. I'm
not quite sure why, I have never had that problem on sparc64 before. I was
also unable to cleanly bootstrap anything newer than gcc47 with the system
compiler (something else I don't recall previously having issues with).

So far with gcc 6.2.0 I have had no issues of note.

I am using the line LDFLAGS=-Wl,-rpath=/usr/local/lib/gcc6 in my make.conf
in the block that specifies using gcc6 in ports. This may not be a good
idea, I'm not sure but it has worked for me thus far. There were some ABI
changes in GCC on sparc64 some time ago so I figured best to use gcc6 libs
on anything built by gcc6. If anyone has any better advice on this I'd love
to hear it.

-Bill