Incremental compilation

Testing for regressions with incremental compilation may require running a command multiple times. The following illustrates an example for #87384 which only generates a warning the second time a build is run with incremental. Previously no warning was emitted.

#![type_length_limit = "95595489"]

pub fn main() {
    println!("Hello, world!");

Create a script


# Exit if any command fails.
set -e

rm -rf incremental
rustc --crate-type lib -C incremental=incremental
echo second
OUTPUT=`rustc --crate-type lib -C incremental=incremental 2>&1`
echo $OUTPUT
! echo "$OUTPUT" | grep \
    "crate-level attribute should be in the root module"

Run this script with:

cargo-bisect-rustc --start 1.54.0 --end 1.55.0 --script ./