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gcc 4_cpp

Character sets Initial processing Overview The preprocessing language Tokenization

Alternatives to Wrapper #ifndef Computed Includes Header Files Include Operation Include Syntax Once-Only Headers Search Path System Headers Wrapper Headers

Argument Prescan C++ Named Operators Common Predefined Macros Concatenation Directives Within Macro Arguments Duplication of Side Effects Function-like Macros Macro Arguments Macro Pitfalls Macros Misnesting Newlines in Arguments Object-like Macros Operator Precedence Problems Predefined Macros Self-Referential Macros Standard Predefined Macros Stringification Swallowing the Semicolon System-specific Predefined Macros Undefining and Redefining Macros Variadic Macros

Conditional Syntax Conditional Uses Conditionals Defined Deleted Code Elif Else If Ifdef

Diagnostics

Line Control

Pragmas

Other Directives

Preprocessor Output

Traditional lexical analysis Traditional macros Traditional miscellany Traditional Mode Traditional warnings

Differences from previous versions Implementation Details Implementation limits Implementation-defined behavior Obsolete Features

Invocation

Environment Variables

gcc / 10. Traditional Mode