Rust安全之数值

数值溢出

编译通过,运行失败
cargo run 1

fn main() {let mut arg = std::env::args().skip(1).map(|x| x.parse::<i32>().unwrap()).next().unwrap();let m_i = i32::MAX - 1;let a = m_i + arg;println!("{:?}", a);
}

thread 'main' panicked at 'attempt to add with overflow', src\bin\rssh3.rs:13:13
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
error: process didn't exit successfully: `target\debug\rssh3.exe 1` (exit code: 101)

编译不通过

fn main() {let m_i = i32::MAX;let a = m_i + 1;println!("{:?}", a);
}

输出

error: this arithmetic operation will overflow--> src\bin\rssh3.rs:9:13|
9 |     let a = m_i + 1;|             ^^^^^^^ attempt to compute `i32::MAX + 1_i32`, which would overflow|= note: `#[deny(arithmetic_overflow)]` on by defaultwarning: `datetime-util` (bin "rssh3") generated 4 warnings
error: could not compile `datetime-util` due to previous error; 4 warnings emitted