gcc

gcc (GNU compiler Collection) is a open-source compiler system. To compile the C program to executables:

gcc -o hello hello.c

It will hide all intermediate steps (pre-process, optimize, linking and etc.) to generate hello directly.

To generate object code,

gcc -c hello.c

It will generate hello.o.

To show all warnings during compliation, you can use -Wall option (-W stands for warning).

gcc -Wall -o hello hello.c