static newUnreachable(id, allPrevSegments) {
		const segment = new CodePathSegment(
			id,
			CodePathSegment.flattenUnusedSegments(allPrevSegments),
			false,
		);

		/*
		 * In `if (a) return a; foo();` case, the unreachable segment preceded by
		 * the return statement is not used but must not be removed.
		 */
		CodePathSegment.markUsed(segment);

		return segment;
	}
Creates an unreachable segment and appends it after the given segments.
@param {string} id An identifier.
@param {CodePathSegment[]} allPrevSegments An array of the previous segments.
@returns {CodePathSegment} The created segment.