Error on "cargo run", runs fine on second call

[azerupi]

Hi sometimes when I run cargo run I get an error.
Sometimes I get a little info:

Compiling rust-learn v0.0.1 (file:///home/mathieu/Programming/Rust/rust-learn)
error: failed to remove /home/mathieu/Programming/Rust/rust-learn/target/debug/math.o: No such file or directory (os error 2)
error: failed to remove /home/mathieu/Programming/Rust/rust-learn/target/debug/math.metadata.o: No such file or directory (os error 2)
An unknown error occurred

But sometimes I just get: An unknown error occurred without explanation.

This happens only when the file has already been built and was modified. By calling cargo run a second time the error disappears (until next modification).

$ cargo --version
cargo 0.2.0-nightly (ac61996 2015-05-17) (built 2015-05-17)

I am running on Arch Linux.

[alexcrichton]

Do you have an example project I could take a peek at as well

[azerupi]

Sure, I think it happens on almost all projects I build. You can try with: https://github.com/azerupi/rust-learn

In src/Numbers/math.rs when I delete some println's, save, build and then put them back, save and build I get that error. But it's weird, I don't get it systematically. It's not such a big deal since everything works by running the command a second time, but you know, some users might be scared by error messages ;)

The exact command I am using is cargo run --bin math

I downloaded cargo through AUR (Arch User Repository). https://aur.archlinux.org/packages/cargo-bin/

And rust through the pacman: https://www.archlinux.org/packages/community/i686/rust/

I also got this error once, but I can't seem to reproduce it:

$ cargo run --bin math
   Compiling rust-learn v0.0.1 (file:///home/mathieu/Programming/Rust/rust-learn)
error: linking with `cc` failed: exit code: 1
note: "cc" "-Wl,--as-needed" "-m64" "-L" "/usr/lib64/rustlib/x86_64-unknown-linux-gnu/lib" "-o" "/home/mathieu/Programming/Rust/rust-learn/target/debug/math" "/home/mathieu/Programming/Rust/rust-learn/target/debug/math.o" "-Wl,--whole-archive" "-lmorestack" "-Wl,--no-whole-archive" "-Wl,--gc-sections" "-pie" "-nodefaultlibs" "/usr/lib/rustlib/x86_64-unknown-linux-gnu/lib/libstd-4e7c5e5c.rlib" "/usr/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcollections-4e7c5e5c.rlib" "/usr/lib/rustlib/x86_64-unknown-linux-gnu/lib/libunicode-4e7c5e5c.rlib" "/usr/lib/rustlib/x86_64-unknown-linux-gnu/lib/librand-4e7c5e5c.rlib" "/usr/lib/rustlib/x86_64-unknown-linux-gnu/lib/liballoc-4e7c5e5c.rlib" "/usr/lib/rustlib/x86_64-unknown-linux-gnu/lib/liblibc-4e7c5e5c.rlib" "/usr/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcore-4e7c5e5c.rlib" "-L" "/home/mathieu/Programming/Rust/rust-learn/target/debug" "-L" "/home/mathieu/Programming/Rust/rust-learn/target/debug/deps" "-L" "/usr/lib64/rustlib/x86_64-unknown-linux-gnu/lib" "-L" "/home/mathieu/Programming/Rust/rust-learn/.rust/lib64/x86_64-unknown-linux-gnu" "-L" "/home/mathieu/Programming/Rust/rust-learn/lib64/x86_64-unknown-linux-gnu" "-Wl,--whole-archive" "-Wl,-Bstatic" "-Wl,--no-whole-archive" "-Wl,-Bdynamic" "-ldl" "-lpthread" "-lrt" "-lgcc_s" "-lpthread" "-lc" "-lm" "-lcompiler-rt"
note: /usr/bin/ld: cannot find /home/mathieu/Programming/Rust/rust-learn/target/debug/math.o: No such file or directory
collect2: error: ld returned 1 exit status

error: aborting due to previous error
Could not compile `rust-learn`.

To learn more, run the command again with --verbose.

[azerupi]

Runnin verbose mode:

$ cargo run --bin math --verbose
   Compiling rust-learn v0.0.1 (file:///home/mathieu/Programming/Rust/rust-learn)
     Running `rustc src/Numbers/math.rs --crate-name math --crate-type bin -g --out-dir /home/mathieu/Programming/Rust/rust-learn/target/debug --emit=dep-info,link -L dependency=/home/mathieu/Programming/Rust/rust-learn/target/debug -L dependency=/home/mathieu/Programming/Rust/rust-learn/target/debug/deps`
error: failed to remove /home/mathieu/Programming/Rust/rust-learn/target/debug/math.o: No such file or directory (os error 2)
error: failed to remove /home/mathieu/Programming/Rust/rust-learn/target/debug/math.metadata.o: No such file or directory (os error 2)
could not rename dep info: "/home/mathieu/Programming/Rust/rust-learn/target/debug/math.d"

Caused by:
  No such file or directory (os error 2)

[alexcrichton]

What version of Cargo and Rust are you using? Unfortunately I can't reproduce this :(

[alexcrichton]

Also, do you perhaps have Cargo running concurrently in the background? (e.g. does your editor run cargo whenever you save?)

[azerupi]

Also, do you perhaps have Cargo running concurrently in the background? (e.g. does your editor run cargo whenever you save?)

That could be it, I am using Atom with some plug-ins for rust. If it is a plug-in that causes this it's probably Atom linter-rust

I will check tomorrow if I still get the error when I disable it.

[azerupi]

My apologies for my late response.

So I uninstalled the plugin I mentioned before, and don't seem to have any errors anymore. It's definitely the cause of all my problems.

I even noticed that it spawned a new rustc process every time I saved.. At some point I had 13 rustc instances running in parallel saturating my processor

[alexcrichton]

Ok! In that case I'm going to close this as a dupe of #354.