Vue version

3.2.35

Link to minimal reproduction

https://codepen.io/Marchcn/pen/GRQvNbZ

Steps to reproduce

See this pls, https://codepen.io/Marchcn/pen/GRQvNbZ and you will get 5 warnings from comsole.

What is expected?

no warnning and faster

What is actually happening?

Warning happend below, and sth cause it very slow in performance

vue.global.js:1616 [Vue warn]: Property undefined was accessed during render but is not defined on instance.

System Info

No response

Any additional comments?

I am migrating my test project from vue2 to vue3, and I need lots of dymatic compile in my project, lots of warning make page performance very bad!

and I found that there are 1.5 times more doms generated in vue3 than vue2 in test project, and less performance

1. There is no version of Vue that supports the :scope syntax on slots.
2. The slot-scope syntax has been deprecated since 2.6 and no longer supported in Vue 3. Please read relevant sections on slots in Vue 3 docs.
3. Runtime compiler performance is likely slower in Vue 3 because it does more work to apply more optimizations (in return for better component update performance). This is by design.

1. There is no version of Vue that supports the :scope syntax on slots.
2. The slot-scope syntax has been deprecated since 2.6 and no longer supported in Vue 3. Please read relevant sections on slots in Vue 3 docs.
3. Runtime compiler performance is likely slower in Vue 3 because it does more work to apply more optimizations (in return for better component update performance). This is by design.

thanks for reply ! I think It made confused as prop has been named 'scope' ， warnning still exists when compiling the emplate defined as <div v-for="i in 5"><slot :p1="{index:i}"></slot></div> and I updated in CodePen here, https://codepen.io/Marchcn/pen/GRQvNbZ, by the way, I found another issue here https://github.com/vuejs/test-utils/issues/549#issuecomment-847956416 with the similar problem, may be helpful for this

This is weird usage because you are using the compiled function inside a custom render function instead of using it directly:

{
  render: function(){
    let r = Vue.compile(`<div v-for="i in 5"><slot :p1="{index:i}">default</slot></div>`);
    return r(this); 
  }
}

I don't know why you are doing this, but you should be doing this instead:

{
  render: Vue.compile(`<div v-for="i in 5"><slot :p1="{index:i}">default</slot></div>`)
}

Runtime-compiled render functions need special handling, but Vue won't know it's runtime-compiled unless it's a function directly returned by Vue.compile.