C1800: Implicit parameter-declaration (missing prototype) for '<FuncName>'

[ERROR]

A function was called without its prototype being declared before.

  void f(void) {

  

    g();

  

  }

  

  This message is only used for C++ or for C if option \c 
  -Wpd, but not Option \c -Ansi is given

  

Prototype the function before calling it. Use void to define a function with no parameters.

  void f(); // better: 'void f(void)'

  

  void g(void);

  

The C the declaration f does not define anything about the parameters of f. The first time f is used, the parameters get defined implicitly. The function g is defined to have no parameters.

The C the declaration f does not define anything about the parameters of f. The first time f is used, the parameters get defined implicitly. The function g is defined to have no parameters.