I see a lot of fellow community members have given technically correct replies. Let me emphasize on the real world scenario. Because It will create an ultimate chaos in crypto market. Below are the possibilities,
1. No block will be mined - it means no transactions will get confirmation from network which will create congestion and increase the transaction fees to an unrealistically high level.
2. Dire consequences on price - bitcoin will be termed as useless because no one would be able to use it. It will result in a huge price crash which may bring down the price to 2 digit level.
3. The halving will be delayed for an unreasonably long time because the halving happens after every 210,000 block. Since no blocks will be mined, the halving will be posponed indefinitely.
In a nutshell, it will create utter chaos in the crypto market.