Reproduction link or steps

let hydrating = false;
let mismatch = false;

function set_hydrating(h) {
	hydrating = h;
}

if (hydrating) {
	mismatch = true;
}

if (mismatch) {
	set_hydrating(true);
}

if (hydrating) {
	console.log("Look ma! I'm hydrating!");
}

There's a more complex reproduction from a real project in vitejs/vite#21944, but I've tried to extract out a minimal reproduction

What is expected?

Rollup dead code eliminates everything in this file

What is actually happening?

Rollup leaves it

System Info

Rolldown 1.0.0-beta.49

Any additional comments?

No response