vite: Vue regression in 2.4.3

Describe the bug

This looks like a Vue or SFC compiler bug, but the only thing that changed (I double-checked by diffing package-lock.json) is Vite being upgraded from 2.4.1 to 2.4.3.

In 2.4.1 my app works fine.

In 2.4.3 it doesn’t start because of this error, straight in my root (App) component:

TypeError: Cannot destructure property 'Component' of 'undefined' as it is undefined.

Where it fails is this SFC generated code:

_createVNode(_component_router_view, null, {
        // Apparently at runtime this lambda receives undefined so destructuring fails
        default: _withCtx(({ Component, route }) => [
        // ...

Reproduction

My App.vue contains this template, which is the (first?) part that fails:

    <router-view v-slot="{ Component, route }">
      <suspense :key="route.path" v-else>
        <component :is="Component" />
        <template #fallback>Loading...</template>
      </suspense>
    </router-view>

System Info

System:
    OS: Windows 10 10.0.18363
    CPU: (12) x64 Intel(R) Core(TM) i7-9850H CPU @ 2.60GHz
    Memory: 5.97 GB / 15.79 GB
  Binaries:
    Node: 15.5.1 - C:\Program Files\nodejs\node.EXE
    Yarn: 1.22.10 - ~\AppData\Roaming\npm\yarn.CMD
    npm: 7.3.0 - C:\Program Files\nodejs\npm.CMD
  Browsers:
    Edge: Spartan (44.18362.1593.0)
    Internet Explorer: 11.0.18362.1
  npmPackages:
    @vitejs/plugin-vue: ^1.2.4 => 1.2.4
    vite: ^2.4.2 => 2.4.3

Used Package Manager

npm

Logs

No response

Validations

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