suggest new bootstrap technique

[aidancully]

Can a "bootstrap" target be added that will create an installable package for cargo that does not rely on having a working cargo installation? Envisioned operation is:

• Creates a target/bootstrap directory (akin to target/package) to hold intermediate files necessary for the bootstrap package.
• Performs a "cargo package"-like operation to store source files, etc., under the bootstrap directory.
• Downloads (or copies) all dependent package source files under the bootstrap directory hierarchy.
• Logs all commands that would be run as part of a cargo build into a file under the bootstrap directory.

The intention is that someone building cargo for the first time on a novel platform (and who doesn't have a supported platform available to run a cross-compile, (ahem) would be able to download a "bootstrap" tarball, run its contained shell script, and end up with a working cargo binary. And in case that didn't work, the shell script would at least contain a record of what a successful compilation process looks like, making it easier to recover from failures.

[MattWindsor91]

👍 for something like this. Tried to get cargo to install on FreeBSD recently, hit a world of pain, and gave up. I know FreeBSD etc. are not priority platforms at the moment, but as someone who does a lot of his development on a FreeBSD box it's vexing to be able to work on C/C++/Ruby projects but not Rust.

[MattWindsor91]

Also, the rapid development cycle of Rust and Cargo means that the current approach of hoping and praying someone's managed to do it and posted a gist of instructions doesn't work out well.

[ebfe]

+1, keeping up with rust/cargo on FreeBSD is really painful at the moment.

[aidancully]

@ebfe @CaptainHayashi https://github.com/aidancully/fakeCargo might help - it's intended to run a build similarly to how cargo does, to help the bootstrap process.

[onibox]

+1 for a better FreeBSD support.

[mneumann]

+1 also required for DragonFlyBSD :)

[csperkins]

I wrote a script that builds Cargo on FreeBSD, by compiling an initial known-good version by hand, and then using that to bootstrap up to the latest version. Details at https://csperkins.org/research/misc/2015-01-02-cargo-freebsd.html if it's useful to others.

[lyuts]

@csperkins Thanks a lot for the link. It is very useful. Just an idea, you can list required dependencies for this bootstrap to succeed. I understand it's a little painful to figure out all of them, but one step a time. textproc/libflate is required. Apologies for the noise in this thread, could find a way to leave a comment in your post.

[csperkins]

I won't have the time to do that for the next few weeks at least, however as a starting point, it bootstraps on a FreeBSD 10.1-RELEASE-p9 machine with only the following packages installed:

bash-4.3.33 =
ca_root_nss-3.18.1 =
cmake-3.1.3 =
cmake-modules-3.1.3 =
curl-7.42.1 =
cvsps-2.1_1 =
expat-2.1.0_2 =
gettext-runtime-0.19.4 =
git-2.3.7 =
gmake-4.1_1 =
indexinfo-0.2.3 =
libexecinfo-1.1_3 =
libffi-3.2.1 =
libflate-2.0 =
libssh2-1.4.3_5,2 =
libunwind-20121006_2 =
p5-Authen-SASL-2.16_1 =
p5-Digest-HMAC-1.03_1 =
p5-Error-0.17023 =
p5-GSSAPI-0.28_1 =
p5-IO-Socket-IP-0.37 =
p5-IO-Socket-SSL-2.012 =
p5-Mozilla-CA-20141217 =
p5-Net-SMTP-SSL-1.02 =
p5-Net-SSLeay-1.68 =
p5-Socket-2.019 =
perl5-5.18.4_14 =
pkg-1.5.1 =
pkgconf-0.9.10 =
python-2.7_2,2 =
python2-2_3 =
python27-2.7.9_1 =
screen-4.2.1_5 =
vim-lite-7.4.691 =

[alexcrichton]

This now exists externally, so closing. Deciding whether to officially include this is #2110