Regression in Command::exec's PATH resolution #55775
Description
Using env_clear() + exec() currently exhibits different behaviour on nightly and stable.
I believe the first nightly to regress was 2018-11-02.
A minimal reproduction is the following code:
use std::process::Command; use std::os::unix::process::CommandExt; fn main() { let mut cmd = Command::new("true"); cmd.env_clear(); let err = cmd.exec(); println!("error: {}", err); }On stable, it prints no error. On nightly, it prints error: No such file or directory (os error 2).
Using strace -e trace=execve, we can see the difference:
# stable execve("/bin/true", ["true"], 0x7fedf1821010 /* 0 vars */) = 0 # nightly execve("true", ["true"], 0x561a58edbb80 /* 0 vars */) = -1 ENOENT (No such file or directory) Meta
$ rustc --version --verbose rustc 1.32.0-nightly (15d770400 2018-11-06) binary: rustc commit-hash: 15d770400eed9018f18bddf83dd65cb7789280a5 commit-date: 2018-11-06 host: x86_64-unknown-linux-gnu release: 1.32.0-nightly LLVM version: 8.0