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 // GC can turn off debug mode in a compartment.

 var dbgs = [];

 var nonDebugGlobals = [];

 var f = gc;

 for (var i = 0; i < 4; i++) {

     // Create two globals, one debuggee.

     var g1 = newGlobal();

     var g2 = g1.eval("newGlobal('same-compartment')");

     var dbg = Debugger(g1);

     dbg.onDebuggerStatement = function () {};

     // Thread a chain of functions through the non-debuggee globals.

     g2.eval("function f() { return g() + 1; }");

     g2.g = f;

     f = g2.f;

     // Root the Debugger objects and non-debuggee globals.

     dbgs[i] = dbg;

     nonDebugGlobals[i] = g2;

 }

 // Call the chain of functions. At the end of the chain is gc. This will

 // collect (some or all of) the debuggee globals, leaving non-debuggee

 // globals. It should disable debug mode in those debuggee compartments.

 nonDebugGlobals[nonDebugGlobals.length - 1].f();

 gc();

 nonDebugGlobals[0].g = function () { return 0; }

 assertEq(nonDebugGlobals[nonDebugGlobals.length - 1].f(), nonDebugGlobals.length);