External toolchain build failing due to missing --sysroot

[NGie Cooper]

On Mon, May 18, 2015 at 1:27 PM, Warner Losh <imp at bsdimp.com> wrote:
>
>> On May 18, 2015, at 2:02 PM, Craig Rodrigues <rodrigc at FreeBSD.org> wrote:
>>
>> On Mon, May 18, 2015 at 12:30 PM, Warner Losh <imp at bsdimp.com> wrote:
>>
>> > On Mar 20, 2015, at 2:10 PM, Craig Rodrigues <rodrigc at FreeBSD.org> wrote:
>> >
>> > Warner,
>> >
>> > I can't get the external toolchain build of CURRENT to work,
>> > because --sysroot seems to be missing in some places.
>>
>> I don’t believe that this has actually never worked, or if it did appear
>> to work, it was only by accident. We have no ability to generate a
>> proper sysroot in the tree today, though we do come close at points.
>> Sean Bruno has been reporting issues with libgcc and external
>> toolchains for months, and I’ve not had the time to track those
>> issues to ground.
>>
>> It seems to work now.  See:
>> https://lists.freebsd.org/pipermail/freebsd-toolchain/2015-April/001660.html
>
> It is quite fragile though. It looks like you are using it in one of the
> configurations that work (hence my accidental comment). But working
> in some configurations is better than it has been in the past...

I'm dealing with this to some extent at $work. Hardcoding paths to
libraries proved to be a painpoint, along with some of the linker
script stuff that was introduced recently:

$ ls -l /usr/lib/libnv.so
lrwxr-xr-x  1 root  wheel  15 Apr  9 12:45 /usr/lib/libnv.so -> /lib/libnv.so.0
$ cat /usr/lib/libc.so
/* $FreeBSD$ */
GROUP ( /lib/libc.so.7 /usr/lib/libc_nonshared.a /usr/lib/libssp_nonshared.a )

These paths are extremely fixed because they're hardcoded...

You can sort of kind of use --sysroot=, but there's a lot of
gymnastics I'm having to go through reinventing the wheel from past
experience with embedded Linux...
Thanks,
-NGie