skylot/jadx · error · JadxRuntimeException

Failed to load method reference for insn: {}

Error message

Failed to load method reference for insn: {}

What it means

In invokePolymorphic(), InsnDataUtils.getMethodRef(insn) returned null. That helper returns null when insn.getIndexType() is not METHOD_REF or no payload/index is resolvable. An invoke-polymorphic instruction (MethodHandle.invoke/invokeExact) must reference a method, so a null ref is fatal.

Source

Thrown at jadx-core/src/main/java/jadx/core/dex/instructions/InsnDecoder.java:601

		inode.addArg(InsnArg.reg(insn, 2, argType));
		return inode;
	}

	private InsnNode cast(InsnData insn, ArgType from, ArgType to) {
		InsnNode inode = new IndexInsnNode(InsnType.CAST, to, 1);
		inode.setResult(InsnArg.reg(insn, 0, to));
		inode.addArg(InsnArg.reg(insn, 1, from));
		return inode;
	}

	private InsnNode invokeCustom(InsnData insn, boolean isRange) {
		return InvokeCustomBuilder.build(method, insn, isRange);
	}

	private InsnNode invokePolymorphic(InsnData insn, boolean isRange) {
		IMethodRef mthRef = InsnDataUtils.getMethodRef(insn);
		if (mthRef == null) {
			throw new JadxRuntimeException("Failed to load method reference for insn: " + insn);
		}
		MethodInfo callMth = MethodInfo.fromRef(root, mthRef);
		IMethodProto proto = insn.getIndexAsProto(insn.getTarget());

		// expand call args
		List<ArgType> args = Utils.collectionMap(proto.getArgTypes(), ArgType::parse);
		ArgType returnType = ArgType.parse(proto.getReturnType());
		MethodInfo effectiveCallMth = MethodInfo.fromDetails(root, callMth.getDeclClass(),
				callMth.getName(), args, returnType);
		return new InvokePolymorphicNode(effectiveCallMth, insn, proto, callMth, isRange);
	}

	private InsnNode invokeSpecial(InsnData insn) {
		IMethodRef mthRef = InsnDataUtils.getMethodRef(insn);
		if (mthRef == null) {
			throw new JadxRuntimeException("Failed to load method reference for insn: " + insn);
		}
		MethodInfo mthInfo = MethodInfo.fromRef(root, mthRef);

View on GitHub (pinned to e738a26571)

Solutions

1. Upgrade JADX (method-ref resolution for polymorphic invokes has seen fixes across releases).
2. Validate the DEX with baksmali to confirm the invoke-polymorphic index resolves to a real method.
3. Skip the class and continue decompiling the rest of the APK.
4. Report the offending instruction offset and class to the JADX tracker.

try {
    jadx.load();
} catch (JadxRuntimeException e) {
    if (e.getMessage().contains("Failed to load method reference")) {
        log.warn("Invoke-polymorphic with unresolved method ref; likely corrupt DEX", e);
    } else throw e;
}

When it happens

Trigger: An invoke-polymorphic instruction whose index type is not METHOD_REF, or whose ICustomPayload / index cannot be cast to IMethodRef — indicating a structurally invalid DEX instruction.

Common situations: Corrupt DEX, a packer that rewrites invoke-polymorphic sites incorrectly, or a malformed constant pool / method handle table.

Related errors

• Failed to decode insn: {}
• Unknown instruction: '{}'
• Failed to get call site for insn: {}
• 'invoke-custom' instruction processing error: {}
• Failed to parse type string: {}

AI-assisted analysis of skylot/jadx@e738a26571 (2026-08-14). Data as JSON: /api/errors/70a72181bbd94505. Report an issue: GitHub.