Hi guys:
I've been reviewing some source code recently which contains many conditional compilation statements, and I found it hard to understand the code not knowing whether some macro is defined or not.

Is there any way to test whether a macro is defined?

#ifdef: http://gcc.gnu.org/onlinedocs/cpp/Ifdef.html

Also note, that if these are the very things that are confusing you, your IDE should be able to track were they are '#define macro_name'... if not, just grep for that with options for ignore case and white space.

If you need to track them at run time, you would have to define a variable and or output to a file when something is defined... or where you choose by using #ifdef...

If you had a section of code that wrote some information to a file for testing these it could be something like

// open file buffer
#ifdef macro1
// write text 'macro1' to file buffer
#endif
#ifdef macro2
// write text 'macro2' to file buffer
#endif
// close file buffer

Of course you could also use this in your help output regarding compile flags.