Volatile variable

Question

Where is a volatile variable stored in the program memory(in which section) ?

Answer 1

In C volatile just tells the compiler - "You don't have enough knowledge to assume the value of this variable hasn't changed". There is no "section" eg BSS, CSS for it.

Consider it a flag to the compiler to prevent certain types of optimisations. Its very handy in embedded programming, where memory at a certain address may "change" due to a hardware device input.

Here's a good explanation: http://www.embedded.com/columns/programmingpointers/174300478?_requestid=137658