MATLAB 2016b Error using mex 'USE_DEFAU​LT_OPERATI​NG_POINT' undeclared

I´m using MATLAB 2016b and want to use a S-Function. But when using

mex myReglerSFcn.c

this happens

>> mex myReglerSFcn.c
Building with 'MinGW64 Compiler (C)'.
Error using mex
D:\...\myReglerSFcn.c: In function 'mdlInitializeSizes':
D:\...\myReglerSFcn.c:100:38: error: 'USE_DEFAULT_OPERATING_POINT' undeclared (first use in
this function)
     ssSetOperatingPointCompliance(S, USE_DEFAULT_OPERATING_POINT);
                                      ^
D:\...\myReglerSFcn.c:100:38: note: each undeclared identifier is reported only once for each
    function it appears in

I used

#include "simstruc.h"

in

myReglerSFcn.c 

the MinGW Compiler is installed an when used with MATLAB 2019a it all works well.

Answer 1

[Annette Mai]

Solved the problem myself:

My original function was based on the example

sfuntmpl_basic.c

which I got from the 2019a version. This example differs to the one from the 2016b version. So I took my function code and put it into the old versions example. This old example differs in various code lines among others the one in the error message.