TIOBE - C Coding Standard

SR: 12.3#11

Synopsis:	Macro arguments must not contain a sequence of tokens which look like a preprocessor directive.
Language:	C
Severity Level:	6
Category:	PREPROCESSING

Description:

Example:

#define STR(text) #text
...
char * msg = STR(
                  #define /* undefined */
                                          );

Here, the presence of the '#define' argument in the STR() macro call is undefined.