C1441: Constant expression shall be integral constant expression

[ERROR]

A constant expression which has to be an integral expression is not integral. A non-integral expression is e.g. a floating constant expression.

  #if 1.   // <&lt; has to be integral!

  

  ;

  

  #endif

  

Use a integral constant expression. Note: if you move this message (to disable/information/warning), the non-integral constant expression is transformed into an integral expression (e.g. 2.3 => 2).