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Analyzer in ASM 6.0 uses only methods newFrame for creation of instances of class Frame. In ASM 6.1.1 there is usage of new Frame - https://gitlab.ow2.org/asm/asm/blob/ASM_6_1_1/asm-analysis/src/main/java/org/objectweb/asm/tree/analysis/Analyzer.java#L276

Test below is a simplified variant of https://github.com/jacoco/jacoco/blob/v0.8.1/org.jacoco.core.test/src/org/jacoco/core/test/validation/StructuredLockingTest.java

Both tests pass with ASM 6.0, but fail with 6.1.1:

import org.junit.Test;
import org.objectweb.asm.ClassReader;
import org.objectweb.asm.tree.ClassNode;
import org.objectweb.asm.tree.MethodNode;
import org.objectweb.asm.tree.analysis.Analyzer;
import org.objectweb.asm.tree.analysis.AnalyzerException;
import org.objectweb.asm.tree.analysis.BasicInterpreter;
import org.objectweb.asm.tree.analysis.BasicValue;
import org.objectweb.asm.tree.analysis.Frame;

import java.io.IOException;

import static org.junit.Assert.assertTrue;

public class ExampleTest {
	@Test
	public void test() throws AnalyzerException, IOException {
		Analyzer<BasicValue> analyzer = new Analyzer<BasicValue>(
				new BasicInterpreter()) {

			@Override
			protected Frame<BasicValue> newFrame(int nLocals, int nStack) {
				return new CustomFrame(nLocals, nStack);
			}

			@Override
			protected Frame<BasicValue> newFrame(
					Frame<? extends BasicValue> src) {
				return new CustomFrame(src);
			}
		};

		ClassNode classNode = new ClassNode();
		new ClassReader(Target.class.getName()).accept(classNode, 0);

		for (MethodNode m : classNode.methods) {
			analyzer.analyze(classNode.name, m);
		}
	}

	static class Target {
		static final Object lock1 = new Object();

		public static void main(String[] args) {
			synchronized (lock1) {
				nop();
			}
		}

		static void nop() {
		}
	}

	static class CustomFrame extends Frame<BasicValue> {
		CustomFrame(int nLocals, int nStack) {
			super(nLocals, nStack);
		}

		CustomFrame(Frame<? extends BasicValue> src) {
			super(src);
		}

		@Override
		public Frame<BasicValue> init(Frame<? extends BasicValue> frame) {
			assertTrue(frame instanceof CustomFrame);
			return super.init(frame);
		}
	}
}