#define cat(a,b) cat2(a,b) #define cat2(a,b) a##b #define FOO 199 #define REQUIRED_FOO 200 #if FOO < REQUIRED_FOO void cat(cat(FOO_is_,FOO), cat(_required_FOO_is_,REQUIRED_FOO))() { #warning Busted! } #endif
Standard input is empty
prog.c: In function 'FOO_is_199_required_FOO_is_200':
prog.c:11:4: warning: #warning Busted! [-Wcpp]
#warning Busted!
^
/usr/lib/gcc/i586-linux-gnu/5/../../../i386-linux-gnu/crt1.o: In function `_start':
(.text+0x18): undefined reference to `main'
collect2: error: ld returned 1 exit status
Standard output is empty