[GROOVY-9822] StackOverflowError in STC

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.0.6
• Fix Version/s: 2.5.14, 3.0.7, 4.0.0-alpha-2
• Component/s: Static compilation
• Assignee: Eric Milles
• Reporter: Christopher Smith
• Created: 19/Nov/20 06:14
• Updated: 07/Dec/20 22:09
• Resolved: 20/Nov/20 12:26

Description

This appears similar to GROOVY-9565, but it's happening in a context that is generics-free as far as I can tell.

Caused by: java.lang.StackOverflowError
    at org.codehaus.groovy.ast.decompiled.DecompiledClassNode.isUsingGenerics (DecompiledClassNode.java:86)
    at org.codehaus.groovy.transform.stc.StaticTypeCheckingSupport.applyGenericsContext (StaticTypeCheckingSupport.java:1880)
    at org.codehaus.groovy.transform.stc.StaticTypeCheckingSupport.applyGenericsContext (StaticTypeCheckingSupport.java:1870)
    at org.codehaus.groovy.transform.stc.StaticTypeCheckingSupport.applyGenericsContext (StaticTypeCheckingSupport.java:1827)
    at org.codehaus.groovy.transform.stc.StaticTypeCheckingSupport.applyGenericsContext (StaticTypeCheckingSupport.java:1816)
    at org.codehaus.groovy.transform.stc.StaticTypeCheckingSupport.applyGenericsContext (StaticTypeCheckingSupport.java:1882)

I managed attempted to trim down the example, but not without referring to the TinkerPop classes (3.4.8). This code triggers the recursion:

import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversalSource
import org.apache.tinkerpop.gremlin.process.traversal.strategy.verification.ReadOnlyStrategy
import org.apache.tinkerpop.gremlin.structure.Graph

import groovy.transform.CompileStatic

@CompileStatic
class Groovy9822 {
    static GraphTraversalSource readOnly(Graph graph) {
        def i = ReadOnlyStrategy.instance()
        graph.traversal().withStrategies(i)
    }
}

Removing the second i so that the varargs is empty and the instance is not passed to withStrategies prevents the error. (In the original code, the invocation was inline with no local variable; I introduced it to make comparative demonstration easier, and its presence seems to be irrelevant.) In case it is relevant, the withStrategies method takes a non-generic TraversalStrategy..., but the class declaration of ReadOnlyStrategy is as follows:

public final class ReadOnlyStrategy extends AbstractTraversalStrategy<TraversalStrategy.VerificationStrategy> implements TraversalStrategy.VerificationStrategy