stringifing #a in define, why is it bad

[katisss]

#define print_int(a) printf("%s : %d\n",#a,(a))
int y=10;
print_int(y)

i am taking a class and have been asked to explain why this is bad... So i guess stringifing #a is the problem. It does work, so why is it dangerous?

[alexchen]

First use code tags. Your code is not Formatted.

#define print_int(a) printf("%s : %d\n",#a,(a))
int y = 10;
print_int(y)

[Ancient Dragon]

>>i am taking a class and have been asked to explain why this is bad
Beats me. If you find out please post the reason so we can all learn something.

[katisss]

hm, http://stackoverflow.com/questions/4868422/stringizing-a-in-define-why-is-it-bad