Program: 58403
Project: 58403
Buggy source:
private static byte[] alterRenderBlocks(String name,String transformedName,byte[] bytes,ClassReader cr){
  String[] names;
  if (LoadingPlugin.runtimeDeobfEnabled) {
    names=new String[]{"String_Node_Str","String_Node_Str","String_Node_Str"};
  }
 else {
    names=new String[]{"String_Node_Str","String_Node_Str","String_Node_Str"};
  }
  name=name.replace('.','/');
  ClassNode cn=new ClassNode(ASM5);
  cr.accept(cn,ClassReader.EXPAND_FRAMES);
  final String sig="String_Node_Str";
  final String Rsig="String_Node_Str";
  final String Ssig="String_Node_Str";
  final String Csig="String_Node_Str";
  final String cc="String_Node_Str";
  final String fd="String_Node_Str";
  l: {
    MethodNode m=null;
    for (    MethodNode n : cn.methods) {
      if (names[0].equals(n.name) && sig.equals(n.desc)) {
        m=n;
        break;
      }
    }
    if (m == null)     break l;
    m.localVariables=null;
    final String[] dirs={"String_Node_Str","String_Node_Str","String_Node_Str","String_Node_Str","String_Node_Str","String_Node_Str","String_Node_Str","String_Node_Str"};
    int di=0;
    for (int i=0, e=m.instructions.size(); i < e; ++i) {
      AbstractInsnNode n=m.instructions.get(i);
      if (n.getType() == AbstractInsnNode.METHOD_INSN) {
        MethodInsnNode mn=(MethodInsnNode)n;
        if (n.getOpcode() == INVOKEINTERFACE && n.getNext().getOpcode() == INVOKEVIRTUAL) {
          if (names[2].equals(mn.name)) {
            if (Csig.equals(mn.desc) && Ssig.equals(((MethodInsnNode)mn.getNext()).desc)) {
              m.instructions.insertBefore(n,new FieldInsnNode(GETSTATIC,fd,dirs[di++],'L' + fd + ';'));
              m.instructions.insertBefore(n,new MethodInsnNode(INVOKEVIRTUAL,cc,"String_Node_Str",Rsig,false));
              m.instructions.remove(n.getNext());
              m.instructions.remove(n);
            }
          }
        }
      }
    }
    if (di == 0)     break l;
    ClassWriter cw=new ClassWriter(ClassWriter.COMPUTE_MAXS);
    cn.accept(cw);
    bytes=cw.toByteArray();
  }
  return bytes;
}

Fixed version (ground truth):
private static byte[] alterRenderBlocks(String name,String transformedName,byte[] bytes,ClassReader cr){
  String[] names;
  if (LoadingPlugin.runtimeDeobfEnabled) {
    names=new String[]{"String_Node_Str","String_Node_Str","String_Node_Str"};
  }
 else {
    names=new String[]{"String_Node_Str","String_Node_Str","String_Node_Str"};
  }
  ClassNode cn=new ClassNode(ASM5);
  cr.accept(cn,ClassReader.EXPAND_FRAMES);
  final String sig="String_Node_Str";
  final String Rsig="String_Node_Str";
  final String Ssig="String_Node_Str";
  final String Csig="String_Node_Str";
  final String cc="String_Node_Str";
  final String fd="String_Node_Str";
  l: {
    MethodNode m=null;
    for (    MethodNode n : cn.methods) {
      if (names[0].equals(n.name) && sig.equals(n.desc)) {
        m=n;
        break;
      }
    }
    if (m == null)     break l;
    m.localVariables=null;
    final String[] dirs={"String_Node_Str","String_Node_Str","String_Node_Str","String_Node_Str","String_Node_Str","String_Node_Str","String_Node_Str","String_Node_Str"};
    int di=0;
    for (int i=0, e=m.instructions.size(); i < e; ++i) {
      AbstractInsnNode n=m.instructions.get(i);
      if (n.getType() == AbstractInsnNode.METHOD_INSN) {
        MethodInsnNode mn=(MethodInsnNode)n;
        if (n.getOpcode() == INVOKEINTERFACE && n.getNext().getOpcode() == INVOKEVIRTUAL) {
          if (names[2].equals(mn.name)) {
            if (Csig.equals(mn.desc) && Ssig.equals(((MethodInsnNode)mn.getNext()).desc)) {
              m.instructions.insertBefore(n,new FieldInsnNode(GETSTATIC,fd,dirs[di++],'L' + fd + ';'));
              m.instructions.insertBefore(n,new MethodInsnNode(INVOKEVIRTUAL,cc,"String_Node_Str",Rsig,false));
              m.instructions.remove(n.getNext());
              m.instructions.remove(n);
            }
          }
        }
      }
    }
    if (di == 0)     break l;
    ClassWriter cw=new ClassWriter(ClassWriter.COMPUTE_MAXS);
    cn.accept(cw);
    bytes=cw.toByteArray();
  }
  return bytes;
}