I am trying to figure out either a bug is rustc version related and want to install rust-1.16 (I am at 1.17 already). Help shows that it should be something like rustup rustup toolchain install stable-yyy-MM-DD
. How do I know what date to use or any other way to install old version?
How to downgrade "stable"?
If that works, it also implies that the rustup
help-message is outdated, which is a legitimate bug in the rust-world.
I’m on mobile, so can’t check myself.
@vchekan, can you confirm if the install 1.16.0
syntax works?
rustup install 1.16.0
should definitely work, I use it all the time for testing against various older releases. It will not touch what rustup considers as the stable
toolchain, as far as I know there’s no way to downgrade that.
In terms of help messages, rustup help install
says
'toolchain' specifies a toolchain name, such as 'stable', 'nightly',
or '1.8.0'. For more information see `rustup help toolchain`.
rustup help toolchains
then also says
Standard release channel toolchain names have the following form:
<channel>[-<date>][-<host>]
<channel> = stable|beta|nightly|<version>
<date> = YYYY-MM-DD
<host> = <target-triple>
'channel' is either a named release channel or an explicit version
number, such as '1.8.0'. Channel names can be optionally appended with
an archive date, as in 'nightly-2014-12-18', in which case the
toolchain is downloaded from the archive for that date.
Obviously @vchekan missed the “or an explicit version number” part somehow, I’m not sure if there’s a simple change to the text that would make that stand out more.
Technically rustup install stable-YYYY-MM-DD
does work as well, with a bit of digging into the manifests I found rustup install stable-2017-03-11
works for installing rustc 1.16.0 (30cf806ef 2017-03-10)
, although I see no reason to use that instead of rustup install 1.16.0
. Again this doesn’t touch what rustup considers to be stable
, it just gives you another stable-2017-03-11
toolchain you can override to.
Huh, that’s a good point. However, the command should work. I’m uncertain why it’s not listed, but I suspect that rustup toolchain install
should work equivalently, though uncertain.
Probably the reason it’s not listed is that rustup install
is an alias of rustup update
, both of which I think are just basically aliases of rustup toolchain install
(which also has another alias at rustup toolchain update
).