Separate Compilation

Question 1

How to convert asm file to o file?

Answer 1

m4 file.asm > file.s
as file.s -o file.o

Question 2

How to convert c file to o file?

Answer 2

gcc -c file.c

Question 3

How to compile 2 o files?

Answer 3

gcc file1.o file2.o -o exec

Question 4

How is object code linked together to create the executable?

Answer 4

Is done by ld (loader), which is usually invoked by gcc as the final step in the compilation process.