Volatile

Definitions

1. A type qualifier (in C, C++, Java, and others) that tells the compiler a variable's value may change at any time without any action being taken by the surrounding code, preventing the compiler from caching it in a register or optimizing away reads and writes.

   In plain English: A label on a variable that tells the computer 'always check the actual value — don't assume it hasn't changed.'

   Example: "Mark that hardware register as volatile or the compiler will optimize out the read and you'll never see the interrupt flag change."

Related Terms

• Mutex
• Swap
• Greenthread
• web worker
• heap
• IPC
• Stack Frame
• Thread Local
• Transactional Memory