Error directive

 

C++

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Technical Specifications

 

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Preprocessor

#if#ifdef#ifndef#else#elif#endif

#define#undef#,## operators

#include__has_include(C++17)

#error

#pragma_Pragma(C++11)

#line

 

Shows the given error message and renders the program ill-formed.

Syntax

#error error_message

Explanation

After encountering the #error directive, an implementation displays the diagnostic message error_message and renders the program ill-formed (the compilation stops).

error_message can consist of several words not necessarily in quotes.

See also

C documentation for Error directive