error: failed to load source for a dependency on 'cc'

[arbitrix]

./x.py build && sudo ./x.py install

Doesn't work.

error: failed to load source for a dependency on 'cc'.

[sanxiyn]

It would be appreciated if you could provide more details, such as your environment. While it doesn't work for you, it works for many people.

I have the same problem on gentoo (using rust overlay and rust-9999 package, which builds rust from git). The build issue was introduced between todays rust version and "rustc 1.26.0-dev (24e679c 2018-03-14)" - this is the last version I have installed.

Here's the error message from the log:

running: /var/tmp/portage/dev-lang/rust-9999/work/rust-git-src/build/x86_64-unknown-linux-gnu/stage0/bin/cargo build --manifest-path /var/tmp/portage/dev-lang/rust-9999/work/rust-git-src/src/bootstrap/Cargo.toml --verbose --locked --frozen
error: failed to load source for a dependency on cc

Caused by:
Unable to update registry https://github.com/rust-lang/crates.io-index

Caused by:
failed to update replaced source registry https://github.com/rust-lang/crates.io-index

Caused by:
failed to read root of directory source: /var/tmp/portage/dev-lang/rust-9999/work/rust-git-src/src/vendor

Caused by:
No such file or directory (os error 2)
Traceback (most recent call last):
File "x.py", line 20, in
bootstrap.main()
File "/var/tmp/portage/dev-lang/rust-9999/work/rust-git-src/src/bootstrap/bootstrap.py", line 800, in main
bootstrap(help_triggered)
File "/var/tmp/portage/dev-lang/rust-9999/work/rust-git-src/src/bootstrap/bootstrap.py", line 780, in bootstrap
build.build_bootstrap()
File "/var/tmp/portage/dev-lang/rust-9999/work/rust-git-src/src/bootstrap/bootstrap.py", line 606, in build_bootstrap
run(args, env=env, verbose=self.verbose)
File "/var/tmp/portage/dev-lang/rust-9999/work/rust-git-src/src/bootstrap/bootstrap.py", line 148, in run
raise RuntimeError(err)

'cc' - I guess it means, it can't find the C++ compiler - I don't have clang installed (though I have llvm-4, llvm-5 and llvm-6). I have gcc-7.3.0 and gcc-6.4.0. cc is gcc-7.3.0. On different system with clang installed the build issue also shows up.

[ExpHP]

The cc in the error message is a bit of a red herring. It means the cc crate; it's searching for a vendored source of the crate and failing.

I don't know too much about the build process for a global install, but here's a similar issue about the (older) Makefile-based build process, which apparently expects to find vendored sources when run with sudo (though a much nicer error is given there). The circumstances here may be the same.

[Randl]

I found a relatively simple solution to this:

1. commented out the following line https://github.com/rust-lang/rust/blob/master/src/bootstrap/bootstrap.py#L792 preventing use of vendored sources
2. run install with sudo -H instead of sudo.

[qknight]

@Randl: you probably are refering to:

rust/src/bootstrap/bootstrap.py

Line 792 in bc87c71

build.use_vendored_sources = True

thanks for pointing out! (your link points to master, and that changed...)