HOWTO: Find out about '#define(d)' constants?

[Andreas Brusinsky <brusinsk@ibdr.inf.tu-dresden.de>]

I know that some of the 'C' constatns are definde by the compiler(gcc)
and others in standard include files of the system and so on.

I have often problems with source distributions of some program and its 
massive use of #ifdef/#if defined (..) statements 

How can I find out about the possible set of '#define(d)' constants
that a source code which should be compiled can use currently (
due to its include files and also system wide)? 

 
        Bye   Brusi

            by           E-Mail: ab2@inf.tu-dresden.de
                         Tel.-priv: 0351-8499347 (Germany/Dresden)
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