error: conflicting types for 'myFunctionOne'

Hello,

The LabWindows/CVI 2013 help page for C Language Extensions appears to show function overloading being supported in the C99 extensions:

 "Function Overloading in C | Yes"

The table in the following link shows the same thing:

http://digital.ni.com/public.nsf/allkb/73AEAD30C8AF681A86257BBB0054A26B

I tried compiling a source file with the following overloaded function definitions with C99 extensions enabled in the Build Options:

 void myFunctionOne(double d) {
  printf ("Value = %f\n", d);
 }

 void myFunctionOne(int d) {
  printf ("Value = %d\n", d);
 }

and I get the error:

 "conflicting types for 'myFunctionOne'

Is function overloading truly supported, and if so, how does one enable it?

Thanks,
Mark B.