Error directive

 

C

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C language

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Preprocessor

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

#define#undef#,## operators

#include

#error

#pragma

#line

 

Shows given message and renders program ill-formed.

Syntax

#error error_message

Explanation

After encountering #error directive, diagnostic message error_message is shown and the program is rendered ill-formed (the compilation is stopped).

error_message can consist of several words not necessarily in quotes.