Say I have a hypothetical Squirtle with 0 base HP.
-His minimum HP at Lv. 100 would be ZERO.
-His maximum HP at Lv. 100 would be ZERO.
-Giving him 252 HP EVs would mean his HP would be ZERO.
- He would always be knocked out. Even Nurse Joy couldn't help him.
Seriously, though. Stats work by multiplication. One of the most basic laws of mathematics is that if you multiply something by zero, the answer is zero. Like this formula:
Why? because zero is not a number. It is a place holder. This means that it cannot be multiplied by anything, therefore not increasing in size or quantity, because it does not exist.
So sorry, but if you had a Pokémon with a base Attack of zero then it would always be zero.