Change https://go.dev/cl/426093 mentions this issue: context: should check comparable of value not type

I'm not sure we should, this change will break user program that set context value with comparable key type, but non-comparable key value (like your example), but never call ctx.Value to get the value.

Also, the context.WithValue doc is also not so clear, it said:

The provided key must be comparable and should not be of type string or any other built-in type to avoid collisions between packages using context.

Not specify key type or key value.

PS: next time, you should wait for discussing in the issue before sending a CL.

i think checking value is comparable is better

Change https://go.dev/cl/554457 mentions this issue: context: WithValue panic for uncomparable value

i just want to understand the reason for it

why the inside the WithValue
we are checking it like this , instead of making this with generics ?

 if !reflectlite.TypeOf(key).Comparable() {
		panic("key is not comparable")
}

if we can make type value as comparable in the function params ?

func WithValue[T comparable](parent context.Context, key T, val any) context.Context {

The WithValue function was added to the API before generics were added to the language. Changing the signature of WithValue now would break the Go 1 compatibility guarantee.

I agree with @cuonglm : I don't think we should change this now. It's a very unusual case, and it's an easy problem to detect and to fix. I don't see a reason to risk breaking existing working code.