MSVC++ Preprocessor - How do I output a define's value with a compiler macro?

Question

I tried #error MY_DEFINE But all that did is echo "MY_DEFINE" when it threw the error.

Thanks!

Answer 1

You can tell the compiler to save the preprocessor output (/E or /EP) and then look at that file. That's usually how I debug problems related to macro expansion.

If you're trying to make some cool error facility for a library, you might be out of luck. I think you'll have a hard time getting the preprocessor to expand a macro into a compile-time message. Perhaps if you combined a template trick that used the macro, you could get it to appear in a cryptic compiler error message.