compiling_and_debugging

gcc file.c
gcc -o file.o file.c
gcc -g -o file.o file.c
gcc -o final.o file1.c file2.c
gcc -c file1.o file1.c
gcc -c file2.o file2.c
gcc -o final.o file1.o file2.o
https://gcc.gnu.org/onlinedocs/gcc-4.9.2/gcc/Warning-Options.html#Warning-Options

syntax is pretty much the same for fortran too, say for f95 compiler
f95 file.f
f95 -o file.exe file.f
https://gcc.gnu.org/wiki/GFortranGettingStarted

r for run
n for next 
print var
b for break

make files