Doubtful
<If an all out, use every last nuke, nuclear exchange occurs between these nations - India will likely survive with about 100 million people and Pakistan will have a few thousand survivors.
While an all out exchange is most unlikely, I doubt that the casualties would be that severe. I could be wrong.
I have read that there are some Indian and Pakastani folks who feel that decimation of their population would have long term positive effect.
Now that is spooky.