# Directive #error

Directive #error

  `#error`

Description

  Throw an error during preprocessing.

  This directive causes a cpp error. It can be used to notify the user that certain functions are missing and similar things.

Note

  Note that this directive will cause cpp() to throw an error at the end of preprocessing, which will cause any compilation to fail.

Example

  #if !constant(Yp) #error Support for NIS not available. #endif

See also

  #warning