Why are preprocessor macros evil and what are the alternatives?

Question

I have always asked this but I have never received a really good answer; I think that almost any programmer before even writing the first \"Hello World\" had encountered a p

Answer 1

Preprocessor macros are not evil when they are used for intended purposes like:

• Creating different releases of the same software using #ifdef type of constructs, for example the release of windows for different regions.
• For defining code testing related values.

Alternatives- One can use some sort of configuration files in ini,xml,json format for similar purposes. But using them will have run time effects on code which a preprocessor macro can avoid.