Compiler build toolchain does not respect build-dir for cargo bash completions

[samkhn]

I am compiling the rust toolchain from source (this includes cargo, clippy, rustdoc, rust-analyzer and src). I am installing it in a custom folder in my home directory.

When I run ./x.py install, it appropriately compiles and installs all of those binaries. However, along the way, the script invokes a copy to /etc/bash_completions.d/cargo and appropriately logs that it doesn't have permissions.

I expect that ./x.py will respect my build-dir argument and try to install the bash completions in build-dir/etc instead of /etc

[samkhn]

My config.toml does not specify a sysconfdir value. By default, it is "/etc". Because it is /etc, it will attempt to install it at root and ignore the build dir prefix: source. This behavior seems a tad bit strange. Shouldn't it be "if the prefix is specified, we'll append sysconfdir" to it similar to the other options "otherwise we'll use default /etc". Then the pathjoining library can resolve join("", "/etc") which is the default and join("/home/user/install/rust", "/etc")?

[jyn514]

we should already be respecting prefix if you set it:

rust/src/bootstrap/install.rs

Line 58 in 95e8b6a

let sysconfdir = prefix.join(default_path(&builder.config.sysconfdir, "/etc"));

can you post the exact error you're seeing, your config.toml, and the commit you're trying to install?

[jyn514]

ok, this replicates the issue:

[build]
extended = true

[install]
prefix = "install-dir"

and the error is

; x install
Installing stage2 cargo (x86_64-unknown-linux-gnu)
install: creating uninstall script at /home/jyn/src/rust2/install-dir/lib/rustlib/uninstall.sh
install: installing component 'cargo'
cp: cannot create regular file '/etc/bash_completion.d/cargo': Permission denied
chmod: cannot access '/etc/bash_completion.d/cargo': No such file or directory
install: error: file creation failed. see logs at '/home/jyn/src/rust2/install-dir/lib/rustlib/install.log'

[jyn514]

ah, i see the problem - prefix.join("/etc") just results in /etc, because it's an absolute path. that seems ... confusing. https://doc.rust-lang.org/stable/std/path/struct.Path.html#method.join

anyway, i'll have a fix up shortly.