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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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/*
 * @test
 * @bug 8321974
 * @summary Test that the TypeAryPtr::_klass field is properly initialized on use.
 * @comment This test only reproduces the issue with release builds of the JVM because
 *          verification code in debug builds leads to eager initialization of the field.
 * @run main/othervm -Xbatch -XX:CompileCommand=compileonly,TestUninitializedKlassField::test*
 *                   -XX:-TieredCompilation TestUninitializedKlassField
 */

public class TestUninitializedKlassField {
    static void test(long array2[]) {
        long array1[] = new long[1];
        // Loop is needed to create a backedge phi that is processed only during IGVN.
        for (int i = 0; i < 1; i++) {
            // CmpPNode::sub will check if classes of array1 and array2 are unrelated
            // and the subtype checks will crash if the _klass field is not initialized.
            if (array2 != array1) {
                array1 = new long[2];
            }
        }
    }

    public static void main(String[] args) {
        for (int i = 0; i < 50_000; ++i) {
            test(null);
        }
    }
}