Internal error on std::process::exit() with --exclude-files

[jyn514]

Note that running without --exclude-files works fine.

$ cargo tarpaulin --exclude-files 'tests/**/*'
[INFO tarpaulin] Running Tarpaulin
[INFO tarpaulin] Building project
[INFO tarpaulin] Launching test
[INFO tarpaulin] running /home/joshua/src/rcc/target/debug/deps/stack_overflow-45c7b9c7d0a485f0

running 1 test
    Finished dev [unoptimized + debuginfo] target(s) in 0.06s
F
failures:

---- run_all stdout ----
testing tests/stack-overflow/decl.c
thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: Os { code: 13, kind: PermissionDenied, message: "Permission denied" }', src/libcore/result.rs:1165:5
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace.


failures:
    run_all

test result: FAILED. 0 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out

Error: "Failed to get test coverage! Error: memory map must have a non-zero length"
[INFO tarpaulin] Launching test
[INFO tarpaulin] running /home/joshua/src/rcc/target/debug/deps/varargs-5b2bb8479dfc0b74
Error: "Tarpaulin experienced an internal error"

[jyn514]

Err ... apparently this is unrelated to --exclude-files because running cargo clean just fixed the problem. Probably related to rust-lang/cargo#7767, sorry for the noise.