C# Language Specification

Variable references

A variable-reference is an expression that is classified as a variable. A variable-reference denotes a storage location that can be accessed both to fetch the current value and to store a new value.

variable-reference:
expression

In C and C++, a variable-reference is known as an lvalue.

5. Atomicity of variable references

Reads and writes of the following data types are atomic: bool, char, byte, sbyte, short, ushort, uint, int, float, and reference types. In addition, reads and writes of enum types with an underlying type in the previous list are also atomic. Reads and writes of other types, including long, ulong, double, and decimal, as well as user-defined types, are not guaranteed to be atomic. Aside from the library functions designed for that purpose, there is no guarantee of atomic read-modify-write, such as in the case of increment or decrement.

6.