Visual Studio C++ System C - Error C2370 Redifinition; different storage class

[Vasundhra]

Build error seems to pick up every constant I defined in top common_params.h with this error.
I have checked that it has not been multiply-included in modules.

[weaknessforcats]

Header files are not to contain constants. The reason is every time you include the header you get another variable of the same name.

Your common constants should be in a .cpp file which is part of your project.

You would have:

//common_params.cpp
 
char* str = "Message";
 
double pi = 3.14159;
 

and the header would be:

//common_params.h
 
extern char* str;
extern double pi;