skylot/jadx · error · JadxRuntimeException

Code generation error after restart

Error message

Code generation error after restart

What it means

Thrown by CodeGen.wrapCodeGen() when a second attempt at code generation also fails. The method first tries codeGenFunc.call(); on exception, if RESTART_CODEGEN is set, it removes the flag and retries. If the retry also throws, it wraps the second exception in a JadxRuntimeException with this message. This is the terminal failure after the anonymous-class-inlining recovery path has been exhausted.

Source

Thrown at jadx-core/src/main/java/jadx/core/codegen/CodeGen.java:52

		return wrapCodeGen(cls, clsGen::makeClass);
	}

	private static ICodeInfo generateJson(ClassNode cls) {
		JsonCodeGen codeGen = new JsonCodeGen(cls);
		String clsJson = wrapCodeGen(cls, codeGen::process);
		return new SimpleCodeInfo(clsJson);
	}

	private static <R> R wrapCodeGen(ClassNode cls, Callable<R> codeGenFunc) {
		try {
			return codeGenFunc.call();
		} catch (Exception e) {
			if (cls.contains(AFlag.RESTART_CODEGEN)) {
				cls.remove(AFlag.RESTART_CODEGEN);
				try {
					return codeGenFunc.call();
				} catch (Exception ex) {
					throw new JadxRuntimeException("Code generation error after restart", ex);
				}
			} else {
				throw new JadxRuntimeException("Code generation error", e);
			}
		}
	}

	private CodeGen() {
	}
}

View on GitHub (pinned to e738a26571)

Solutions

1. Report the class to the jadx project with the full stack trace (the inner cause exception is the key diagnostic).
2. Switch to DecompilationMode.FALLBACK which bypasses many of the aggressive transforms that trigger restarts.
3. Exclude the problematic class from decompilation.

Example fix

// before
//   JadxArgs args = new JadxArgs();
//   args.setDecompilationMode(DecompilationMode.AUTO);
// after
//   args.setDecompilationMode(DecompilationMode.FALLBACK);

// Set fallback mode to avoid the restart-triggering code paths
JadxArgs args = new JadxArgs();
args.setDecompilationMode(DecompilationMode.FALLBACK);
// This bypasses anonymous class inlining that causes RESTART_CODEGEN

try {
    jadxDecompiler.decompile();
} catch (JadxRuntimeException e) {
    if (e.getMessage().equals("Code generation error after restart")) {
        logger.error("Codegen failed after restart. The cause exception has the root failure.", e);
        // Examine e.getCause() for the actual failure on the second attempt
    }
    throw e;
}

When it happens

Trigger: Anonymous class inlining triggers RESTART_CODEGEN, the class codegen restarts, and the restart attempt also encounters an exception. The original exception from the first attempt is lost; only the second (restart) exception is captured.

Common situations: Complex nested anonymous classes where the conversion-to-inner-class recovery still cannot generate valid code. Obfuscated code with unusual constructor or lambda patterns.

Related errors

• Method generation error
• Anonymous inner class unlimited recursion detected. Convert
• Code generation error
• Error generate insn:
• Constructor 'self' invoke must be removed!

AI-assisted analysis of skylot/jadx@e738a26571 (2026-08-14). Data as JSON: /api/errors/05fe60a67ba50ee7. Report an issue: GitHub.