APT problem: StackOverflowError in RoundDispatcher.handleProcessor

[kriegaex]

This issue came up in dev-aspectj/aspectj-maven-plugin#108, but it is not a problem concerning the Maven plugin. Instead, it seems to be related to annotation processing (APT) support for AJC:

There is an annotation processor on the classpath, namely com.querydsl:querydsl-apt:5.0.0-jakarta. It contains a file META-INF/services/javax.annotation.processing.Processor with the following content:

com.querydsl.apt.jpa.JPAAnnotationProcessor

That annotation processor handles the @jakarta.persistence.MappedSuperclass annotations found on two classes in the sample repository.

While Javac (used by Maven Compiler Plugin) can correctly generate code, it seems as if the annotation processor throws off AJC like this (error message with additional line breaks):

...\baz\src\main\java\com\foobar\showme\baz\TimestampedJPADurable.java [error]
Internal compiler error: java.lang.Exception:
java.lang.StackOverflowError at 
  org.aspectj.org.eclipse.jdt.internal.compiler.apt.dispatch.RoundDispatcher.handleProcessor(RoundDispatcher.java:172)
(no source information available)

A reproducer is at https://github.com/zenbones/showme. Thanks to @zenbones for reporting the problem.

See also dev-aspectj/aspectj-maven-plugin#108 (comment) for an AspectJ Maven workaround which can also be applied to the AJC command line: letting Javac take care of annotation processing and then using -proc:none for AJC.

[kriegaex]

I debugged into AJC, because unfortunately the upstream Eclipse Jave Compiler (ACJ) underneath AJC does not log a full stack trace for the stack overflow error. Here it is:

java.lang.StackOverflowError
	at com.querydsl.apt.ExtendedTypeFactory$2.visitBase(ExtendedTypeFactory.java:207)
	at com.querydsl.apt.ExtendedTypeFactory$2.visitTypeVariable(ExtendedTypeFactory.java:252)
	at com.querydsl.apt.ExtendedTypeFactory$2.visitTypeVariable(ExtendedTypeFactory.java:201)
	at org.aspectj.org.eclipse.jdt.internal.compiler.apt.model.TypeVariableImpl.accept(TypeVariableImpl.java:77)
	at java.compiler@19.0.1/javax.lang.model.util.AbstractTypeVisitor6.visit(AbstractTypeVisitor6.java:91)
	at com.querydsl.apt.ExtendedTypeFactory$2.visitTypeVariable(ExtendedTypeFactory.java:254)
	at com.querydsl.apt.ExtendedTypeFactory$2.visitTypeVariable(ExtendedTypeFactory.java:201)
	at org.aspectj.org.eclipse.jdt.internal.compiler.apt.model.TypeVariableImpl.accept(TypeVariableImpl.java:77)
	at java.compiler@19.0.1/javax.lang.model.util.AbstractTypeVisitor6.visit(AbstractTypeVisitor6.java:91)
	at com.querydsl.apt.ExtendedTypeFactory$2.visitTypeVariable(ExtendedTypeFactory.java:254)
	at com.querydsl.apt.ExtendedTypeFactory$2.visitTypeVariable(ExtendedTypeFactory.java:201)
       (and many more repetitions of the last 4 lines)

It would be interesting to see if that works in plain vanilla ECJ or is AJC-specific. I will try that next after work.

[kriegaex]

Update (CC @zenbones): I quickly checked during a break, and it definitely is not an AJC problem. The same occurs when compiling the project with plain vanilla ECJ 3.31.0. And also there -proc:none makes the project compile, but of course in that case no code generation via APT takes place.

Update: Bug ticket eclipse-jdt/eclipse.jdt.core#565 created.

[kriegaex]

According to eclipse-jdt/eclipse.jdt.core#565 (comment), the JDT Core issue should be fixed since ECJ 3.39.0 (Eclipse 2024-09). Upgrading the version in the AspectJ fork should fix it in ACJ, too. To do: verify.