now the thing is, reading cookies in the route will automatically switch to dynamic rerendering right?

i relied on this in next 14

but now it seems like this has changed?

callstack doesn't reference the source of the issue, only tells me the error

Visting that link in the error gives:

Objects are not valid as a React child (found: object with keys {$$typeof, type, key, ref, props}). If you meant to render a collection of children, use an array instead.

which is the actual error that happened while building. Is your 500 page custom in any way, and if so, could you share the code?

i dont have a 500 page

i only migrated to v15

i changed nothing

the things that was changed by the codemod is switchtig to async cookies and headers and useActionState

thats it

Do you have a custom _error page? Either in pages router or app router. That would be the place it's coming from (either a custom one that is present, or the default one)

nope

the weird thing is

sometimes it happens in /500

sometimes in /404

im on ice

usually im the one helping lmao

and i need to get this project finished in 1 week

im cooked

Yeah, it's definitely in the error page, which renders for both.

no global-error page either?

nope

this is the only things i have

are you using app router or pages?

ill remove loading.tsx and try again

app router

ofc

it has something to do with nextjs trying to prerender the route

even tho in my root layout i use cookies

so shouldnt that automatically switch to dynamic rendering?

ok now i forced nextjs to prerender my root layout dynamically

web:build:    Generating static pages (0/8) ...
web:build:    Generating static pages (2/8) 

the amout of static pages was reduced to the half and it stops on 2

then the same error but this time with /404

web:build: Error occurred prerendering page "/404". Read more: https://nextjs.org/docs/messages/prerender-error
web:build: Error: Minified React error #31; visit https://reactjs.org/docs/error-decoder.html?invariant=31&args[]=object%20with%20keys%20%7B%24%24typeof%2C%20type%2C%20key%2C%20ref%2C%20props%7D for the full message or use the non-minified dev environment for full errors and additional helpful warnings.

its just random

no i get the error on page 0/8

so, the not-found.tsx will still render the outer layout.tsx. I'd look there. Additionally, the error mesage at that linkto reactjs.org is indicating that an object is trying to be rendered as a child. Something like <div>{ thisIsAnObject }</div>

what am i suppose to do with that?

isnt that how nextjs rsc works

i did that like idk 1000 times

in my code

That is erroneous only if what you're passing as a child is not a react component. It's perfectly valid if it is a component (a string, a component, an array of both, etc). The error your getting is because somewhere, something that is not a component is attempting to be rendered.

Like, <div>{ "hello" }</div> is perfectly fine, but <div>{ { key: "value" } }</div> is not, because an object is not a valid react child.

u mean rendering a deeply nested json without parsing it to a string first?

if so thats really weird cause on v14 everything was working fine

i mean not only on v14 literally on every version

im not really sure its a problem on my side

so i probably will debug it further and if i dont get a solution ill head over to githu issues

It's probably some change in a value being passed somewhere. I'd read through and do everything in https://nextjs.org/docs/app/building-your-application/upgrading/version-15

If your project has any external react dependencies, check if there are any breaking changes in them. If you're using react 19, this may be difficult to find or unsupported for some of your dependencies, and you might need to fall back to react 18.

Checking in, did you have any luck?

unfortunately not

i ended up reversing back to v14

for now

once i have time ill try to resolve this issue step by step

i have some libraries written by myself (i18n, auth etc) the issue could be in one of them so ill try to debug it once i have time