Props do not respect optionality in components defined using `defineComponent` with a generic function signature

[cernymatej]

Vue version

3.5.13

Link to minimal reproduction

https://play.vuejs.org/#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

Steps to reproduce

Open the reproduction and have a look at the type error on the <OptionalGenericExample /> component in the template.

I defined an optional prop:

interface Props<T> {
  val?: T
}

and used it in a generic component:

const OptionalGenericExample = defineComponent(
  <T extends string>(props: Props<T>) => {
    return () => h('div', [
      'OptionalExample'
    ])
  },
  {
    props: ['val']
  }
)

When used in the template without providing the prop, the following error is shown:

Argument of type '{}' is not assignable to parameter of type '{ val: any; } & VNodeProps & AllowedComponentProps & ComponentCustomProps & Record<string, unknown>'.
  Property 'val' is missing in type '{}' but required in type '{ val: any; }'.

<template>
  <OptionalGenericExample />
</template>

This doesn't happen when the component is not generic.

What is expected?

I would expect no error to be present, since the prop is optional and doesn't need to be specified.

What is actually happening?

A type error is present.

System Info

Any additional comments?

No response