<http://news.gmane.org/find-root.php?message_id=%3cCADTL0obsq43X0%5f%3dgwPCZp6O3W1kq6yZan9eP8N3MbkFT2iVXmg%40mail.gmail.com%3e>I
have used -Wall .
It is my Makefile used to compile the program.
all:
gcc -g -Wall calc.c -o calc `pkg-config --cflags --libs gtk+-3.0`
Regards
Aravindhan .K