In Eclipse 2021-03 and Eclipse Groovy Development Tools 4.2.0.v202106140218-e2103 i get this error

eclipse.buildId=4.19.0.I20210303-1800
java.version=15.0.1
java.vendor=AdoptOpenJDK
BootLoader constants: OS=win32, ARCH=x86_64, WS=win32, NL=de_AT
Framework arguments: -product org.eclipse.epp.package.jee.product
Command-line arguments: -os win32 -ws win32 -arch x86_64 -product org.eclipse.epp.package.jee.product

org.eclipse.jdt.groovy.core
Error
Tue Jun 15 13:38:11 CEST 2021
Groovy compiler error

BUG! exception in phase 'semantic analysis' in source unit '/filepath/filenname.groovy' unexpected NullPointerException
at org.codehaus.groovy.control.CompilationUnit.applyToPrimaryClassNodes(CompilationUnit.java:1135)
at org.codehaus.groovy.control.CompilationUnit.doPhaseOperation(CompilationUnit.java:635)
at org.codehaus.groovy.control.CompilationUnit.processPhaseOperations(CompilationUnit.java:614)
at org.codehaus.groovy.control.CompilationUnit.compile(CompilationUnit.java:591)
at org.codehaus.jdt.groovy.internal.compiler.ast.GroovyCompilationUnitDeclaration.processToPhase(GroovyCompilationUnitDeclaration.java:226)
at org.codehaus.jdt.groovy.internal.compiler.ast.GroovyCompilationUnitDeclaration.resolve(GroovyCompilationUnitDeclaration.java:609)
at org.eclipse.jdt.internal.core.hierarchy.HierarchyResolver.resolve(HierarchyResolver.java:882)
at org.eclipse.jdt.internal.core.hierarchy.IndexBasedHierarchyBuilder.buildForProject(IndexBasedHierarchyBuilder.java:266)
at org.eclipse.jdt.internal.core.hierarchy.IndexBasedHierarchyBuilder.buildFromPotentialSubtypes(IndexBasedHierarchyBuilder.java:377)
at org.eclipse.jdt.internal.core.hierarchy.IndexBasedHierarchyBuilder.build(IndexBasedHierarchyBuilder.java:167)
at org.eclipse.jdt.internal.core.hierarchy.TypeHierarchy.compute(TypeHierarchy.java:323)
at org.eclipse.jdt.internal.core.hierarchy.TypeHierarchy.refresh(TypeHierarchy.java:1319)
at org.eclipse.jdt.internal.core.CreateTypeHierarchyOperation.executeOperation(CreateTypeHierarchyOperation.java:94)
at org.eclipse.jdt.internal.core.JavaModelOperation.run(JavaModelOperation.java:740)
at org.eclipse.jdt.internal.core.JavaModelOperation.runOperation(JavaModelOperation.java:806)
at org.eclipse.jdt.internal.core.SourceType.newTypeHierarchy(SourceType.java:950)
at org.eclipse.jdt.internal.core.SourceType.newTypeHierarchy(SourceType.java:907)
at org.eclipse.jdt.internal.ui.javaeditor.codemining.JavaImplementationCodeMining.countTypeImplementations(JavaImplementationCodeMining.java:165)
at org.eclipse.jdt.internal.ui.javaeditor.codemining.JavaImplementationCodeMining.lambda$0(JavaImplementationCodeMining.java:83)
at java.base/java.util.concurrent.CompletableFuture$AsyncRun.run(CompletableFuture.java:1800)
at java.base/java.util.concurrent.CompletableFuture$AsyncRun.exec(CompletableFuture.java:1792)
at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:290)
at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1016)
at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1665)
at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1598)
at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:183)
Caused by: java.lang.NullPointerException: Cannot invoke "org.codehaus.groovy.ast.FieldNode.getType()" because the return value of "org.codehaus.groovy.ast.ClassNode.getDeclaredField(String)" is null
at org.codehaus.groovy.classgen.InnerClassVisitor.insertThis0ToSuperCall(InnerClassVisitor.java:309)
at org.codehaus.groovy.classgen.InnerClassVisitor.passThisReference(InnerClassVisitor.java:287)
at org.codehaus.groovy.classgen.InnerClassVisitor.visitConstructorCallExpression(InnerClassVisitor.java:141)
at org.codehaus.groovy.ast.expr.ConstructorCallExpression.visit(ConstructorCallExpression.java:46)
at org.codehaus.groovy.ast.CodeVisitorSupport.visitReturnStatement(CodeVisitorSupport.java:124)
at org.codehaus.groovy.ast.ClassCodeVisitorSupport.visitReturnStatement(ClassCodeVisitorSupport.java:302)
at org.codehaus.groovy.ast.stmt.ReturnStatement.visit(ReturnStatement.java:49)
at org.codehaus.groovy.ast.CodeVisitorSupport.visitBlockStatement(CodeVisitorSupport.java:86)
at org.codehaus.groovy.ast.ClassCodeVisitorSupport.visitBlockStatement(ClassCodeVisitorSupport.java:256)
at org.codehaus.groovy.ast.stmt.BlockStatement.visit(BlockStatement.java:69)
at org.codehaus.groovy.ast.ClassCodeVisitorSupport.visitClassCodeContainer(ClassCodeVisitorSupport.java:164)
at org.codehaus.groovy.classgen.InnerClassVisitor.visitConstructorOrMethod(InnerClassVisitor.java:110)
at org.codehaus.groovy.ast.ClassCodeVisitorSupport.visitMethod(ClassCodeVisitorSupport.java:185)
at org.codehaus.groovy.ast.ClassNode.visitContents(ClassNode.java:1207)
at org.codehaus.groovy.ast.ClassCodeVisitorSupport.visitClass(ClassCodeVisitorSupport.java:56)
at org.codehaus.groovy.classgen.InnerClassVisitor.visitClass(InnerClassVisitor.java:80)
at org.codehaus.groovy.control.CompilationUnit$9.call(CompilationUnit.java:222)
at org.codehaus.groovy.control.CompilationUnit.applyToPrimaryClassNodes(CompilationUnit.java:1130)
... 25 more