Why Don\'t C Compilers Generate Default Comparison Operators (operator== and operator!=)?

Why Do C Compilers Avoid Generating Default Comparison Operators?

While C compilers provide default constructors, copy constructors, destructors, and assignment operators, they intentionally exclude comparison operators such as operator== and operator!=. This design decision stems from concerns raised by C creator Bjarne Stroustrup regarding the potential pitfalls of automatically generated copy operations.

Stroustrup expressed his reservations in "The Design and Evolution of C ," stating that he considers default copy operations to be undesirable and actively prevents their use in many of his classes. This reluctance arose from C 's inheritance from C, where default copy constructors and assignment operators were often employed. However, these default operations could lead to unexpected behavior when applied to classes with complex or delicate internals.

In the absence of default comparison operators, the compiler forcibly requires explicit definitions for operator== and operator!=. This ensures that developers thoroughly consider the implications of class comparison and define custom operators that accurately reflect their intended behavior. This approach encourages developers to make informed decisions about class comparisons rather than relying on implicit or potentially erroneous compiler-generated code.

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