On 26 December 2010 06:58, ali hagigat wrote: > Please look at the following program: > > main(){ > printf("func1= %d\n", func1(10)); > } > > /root/tmp3> gcc -c -o prog1.o prog1.c > prog1.c: In function ‘main’: > prog1.c:6: warning: incompatible implicit declaration of built-in > function ‘printf’ > ------------------------------------------------------------------- > Why the declaration of printf is incomplete? http://c-faq.com/varargs/protos.html