jdk-24/test/nashorn/script/basic/es6/JDK-8168373.js

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/**
 * JDK-8168373: don't emit conversions for symbols outside their lexical scope
 *
 * @test
 * @run
 * @option --language=es6
 */

function p() { return false } // "predicate"
function r(x) { return x } // "read"

(function() {
  try { // Try creates control flow edges from assignments into catch blocks.
    // Lexically scoped, never read int variable (undefined at catch block) but still with a cf edge into catch block.
    // Since it's never read, it's not written either (Nashorn optimizes some dead writes).
    let x = 0;
    if (p()) { throw {}; } // We need `p()` so this block doesn't get optimized away, for possibility of a `throw`
    x = 0.0; // change the type of x to double
    r(x); // read x otherwise it's optimized away
  } catch (e) {} // under the bug, "throw" will try to widen unwritten int x to double for here and cause a verifier error
})()