حالات التسابق

في هذا الدرس

spot a race and a check-then-act bug.

الموضوعات المخطط لها

• A race condition: the result depends on thread timing.
• count++ is read, add, write: three steps, so updates can be lost.
• Check-then-act: if (stock > 0) stock--; can oversell when two threads pass the check.
• Races are intermittent; passing tests do not prove safety.
• Shared mutable state is the root; remove sharing or mutation, or guard it.