Compiling this code:

public class X {
    {
        void foo() {
            System.out.println("foo in init block");
        }
        foo();
    }
 
    public static void main(String [] args) {
        new X();
    }
}

results in:

An exception has occurred in the compiler (14-internal). Please file a bug against the Java compiler via the Java bug reporting page (http://bugreport.java.com) after checking the Bug Database (http://bugs.java.com) for duplicates. Include your program, the following diagnostic, and the parameters passed to the Java compiler in your report. Thank you.
java.lang.NullPointerException
at jdk.compiler/com.sun.tools.javac.code.Symbol$MethodSymbol.<init>(Symbol.java:1732)
at jdk.compiler/com.sun.tools.javac.comp.MemberEnter.visitMethodDef(MemberEnter.java:183)
at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:876)
at jdk.compiler/com.sun.tools.javac.comp.MemberEnter.memberEnter(MemberEnter.java:163)
at jdk.compiler/com.sun.tools.javac.comp.Attr.visitMethodDef(Attr.java:977)
at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:876)
at jdk.compiler/com.sun.tools.javac.comp.Attr.attribTree(Attr.java:666)
at jdk.compiler/com.sun.tools.javac.comp.Attr.attribStat(Attr.java:738)
at jdk.compiler/com.sun.tools.javac.comp.Attr.attribStats(Attr.java:756)
at jdk.compiler/com.sun.tools.javac.comp.Attr.visitBlock(Attr.java:1299)
at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCBlock.accept(JCTree.java:1030)
at jdk.compiler/com.sun.tools.javac.comp.Attr.attribTree(Attr.java:666)
at jdk.compiler/com.sun.tools.javac.comp.Attr.attribStat(Attr.java:738)
at jdk.compiler/com.sun.tools.javac.comp.Attr.attribClassBody(Attr.java:4861)
at jdk.compiler/com.sun.tools.javac.comp.Attr.attribClass(Attr.java:4752)
at jdk.compiler/com.sun.tools.javac.comp.Attr.attribClass(Attr.java:4681)
at jdk.compiler/com.sun.tools.javac.comp.Attr.attrib(Attr.java:4626)
at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.attribute(JavaCompiler.java:1346)
at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.compile(JavaCompiler.java:972)
at jdk.compiler/com.sun.tools.javac.main.Main.compile(Main.java:318)
at jdk.compiler/com.sun.tools.javac.main.Main.compile(Main.java:176)
at jdk.compiler/com.sun.tools.javac.Main.compile(Main.java:57)
at jdk.compiler/com.sun.tools.javac.Main.main(Main.java:43)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at com.intellij.rt.execution.application.AppMainV2.main(AppMainV2.java:131)