IndexOutOfBoundsException in AtmLubVisitor.visitIntersection_Intersection

[cushon]

import java.util.Optional;

abstract class X {
  <T extends First & Second> Optional<T> a(boolean b, Class<T> clazz) {
    return b ? Optional.empty() : Optional.of(b(clazz));
  }

  abstract <T extends First & Second> T b(Class<T> clazz);

  interface First {}

  interface Second {}
}

$ ./checker-framework-3.42.0/checker/bin/javac -processor nullness X.java
error: Error in AnnotatedTypeMirror.fromExpression(KeyForAnnotatedTypeFactory, b ? Optional.empty() : Optional.of(b(clazz))): Index 0 out of bounds for length 0
  ; The Checker Framework crashed.  Please report the crash.  Version: Checker Framework 3.42.0.
  Compilation unit: X.java
  Last visited tree at line 3 column 1:
  abstract class X {
  Exception: java.lang.IndexOutOfBoundsException: Index 0 out of bounds for length 0; java.lang.IndexOutOfBoundsException: Index 0 out of bounds for length 0
        at java.base/jdk.internal.util.Preconditions.outOfBounds(Preconditions.java:64)
        at java.base/jdk.internal.util.Preconditions.outOfBoundsCheckIndex(Preconditions.java:70)
        at java.base/jdk.internal.util.Preconditions.checkIndex(Preconditions.java:248)
        at java.base/java.util.Objects.checkIndex(Objects.java:372)
        at java.base/java.util.ArrayList.get(ArrayList.java:460)
        at org.checkerframework.framework.util.AtmLubVisitor.visitIntersection_Intersection(AtmLubVisitor.java:374)
        at org.checkerframework.framework.util.AtmLubVisitor.visitIntersection_Intersection(AtmLubVisitor.java:33)
        at org.checkerframework.framework.util.AtmCombo.accept(AtmCombo.java:400)
        at org.checkerframework.framework.type.visitor.AbstractAtmComboVisitor.visit(AbstractAtmComboVisitor.java:34)
        at org.checkerframework.framework.util.AtmLubVisitor.visitTypevar_Typevar(AtmLubVisitor.java:307)
        at org.checkerframework.framework.util.AtmLubVisitor.visitTypevar_Typevar(AtmLubVisitor.java:33)
        at org.checkerframework.framework.util.AtmCombo.accept(AtmCombo.java:612)
        at org.checkerframework.framework.type.visitor.AbstractAtmComboVisitor.visit(AbstractAtmComboVisitor.java:34)
        at org.checkerframework.framework.util.AtmLubVisitor.lubTypeArgument(AtmLubVisitor.java:263)
        at org.checkerframework.framework.util.AtmLubVisitor.visitDeclared_Declared(AtmLubVisitor.java:208)
        at org.checkerframework.framework.util.AtmLubVisitor.visitDeclared_Declared(AtmLubVisitor.java:33)
        at org.checkerframework.framework.util.AtmCombo.accept(AtmCombo.java:312)
        at org.checkerframework.framework.type.visitor.AbstractAtmComboVisitor.visit(AbstractAtmComboVisitor.java:34)
        at org.checkerframework.framework.util.AtmLubVisitor.lub(AtmLubVisitor.java:72)
        at org.checkerframework.framework.util.AnnotatedTypes.leastUpperBound(AnnotatedTypes.java:788)
        at org.checkerframework.framework.type.TypeFromExpressionVisitor.visitConditionalExpression(TypeFromExpressionVisitor.java:182)
        at org.checkerframework.framework.type.TypeFromExpressionVisitor.visitConditionalExpression(TypeFromExpressionVisitor.java:77)
        at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCConditional.accept(JCTree.java:1413)
        at jdk.compiler/com.sun.source.util.SimpleTreeVisitor.visit(SimpleTreeVisitor.java:80)

[smillst]

Thanks for reporting. This has already been fixed in master. (#6441 )