# Error directive

From cppreference.com
< c‎ | preprocessor

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.

### Example

Run this code

    #if __STDC__ != 1
    #  error "Not a standard compliant compiler"
    #endif

    #include <stdio.h>
    int main (void)
    {
        printf("The compiler used conforms to the ISO C Standard !!");
    }

Possible output:

    The compiler used conforms to the ISO C Standard !!

### References

- C11 standard (ISO/IEC 9899:2011):

  - 6.10.5 Error directive (p: 174)

- C99 standard (ISO/IEC 9899:1999):

  - 6.10.5 Error directive (p: 159)

- C89/C90 standard (ISO/IEC 9899:1990):

  - 3.8.5 Error directive

### See also

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