C:\_32\C>type try.c

#include <stdio.h>

int main (void) {
#define FOO(s) printf("%s\n", "" s "");
 FOO(VER);

 return 0;
}

C:\_32\C>gcc -o try.exe -DVER="\"0.1\"" try.c

C:\_32\C>try
0.1

C:\_32\C>gcc -o try.exe -DVER=0.1 try.c
try.c: In function 'main':
try.c:5:2: error: expected ')' before numeric constant