}
			c <- struct{}{}
		}()
		runtime.Goexit()
	}()
	// Note: if the defer fails to run, we will get a deadlock here
	<-c
}

func TestGoNil(t *testing.T) {
	output := runTestProg(t, "testprog", "GoNil")
	want := "go of nil func value"
	if !strings.Contains(output, want) {
		t.Fatalf("output:\n%s\n\nwant output containing: %s", output, want)
	}
}

func TestMainGoroutineID(t *testing.T) {

		}

		// Recognize a few common expressions that can be evaluated within
		// the wrapper, so we don't need to allocate space for them within
		// the closure.
		switch arg.Op() {
		case ir.OLITERAL, ir.ONIL, ir.OMETHEXPR, ir.ONEW:
			return
		case ir.ONAME:
			arg := arg.(*ir.Name)
			if arg.Class == ir.PFUNC {
				return // reference to global function
			}
		case ir.OADDR:
			arg := arg.(*ir.AddrExpr)

		ir.OANDNOT,
		ir.OBITNOT,
		ir.OCONV,
		ir.OCONVIFACE,
		ir.OCONVNOP,
		ir.ODIV,
		ir.ODOT,
		ir.ODOTTYPE,
		ir.OLITERAL,
		ir.OLSH,
		ir.OMOD,
		ir.OMUL,
		ir.ONEG,
		ir.ONIL,
		ir.OOR,
		ir.OOROR,
		ir.OPAREN,
		ir.OPLUS,
		ir.ORSH,
		ir.OSUB,
		ir.OXOR:
		return false
	}

	// Be conservative.
	return true
}

// expand append(l1, l2...) to

	if cond.Op() == ir.OBYTES2STR && allCaseExprsAreSideEffectFree(sw) {
		cond := cond.(*ir.ConvExpr)
		cond.SetOp(ir.OBYTES2STRTMP)
	}

	cond = walkExpr(cond, sw.PtrInit())
	if cond.Op() != ir.OLITERAL && cond.Op() != ir.ONIL {
		cond = copyExpr(cond, cond.Type(), &sw.Compiled)
	}

	base.Pos = lno

	s := exprSwitch{
		pos:      lno,
		exprname: cond,
	}

	var defaultGoto ir.Node
	var body ir.Nodes