MEGA.md

Let's Make Exceptions Great Again (M.E.G.A.)

Introduction

What is wrong with C++ exceptions?

1. exceptions are expensive

• unknown price (space/performance) and behaviour
  • heap allocated
• ironically, stack unwinding in C++ (a compiled language) is executed by dwarf interpreter
• also, stack unwinding can allocate memory

2. exception costs are unpredictable
3. exceptions prevent compiler from using certain optimizations
4. unreliable
5. proposals to change exceptions (Herb's "Deterministic exceptions", Outcome pattern)