Compile and link exercise¶

A basic Fortran compile and link excercise on Tetralith¶

Download the code and clear your environment

git clone https://github.com/annlew/compile_exercise.git

cd compile_exercise/compile

module purge

In this folder you will find a basic hello_world.f90 file and some Makefiles

Open the file Makefile and check what’s inside.

Try to compile:

make

What happened?

Now, load a build environment and run make again, e.g.:

module load buildenv-intel/2023a-eb
make

What is the difference? You might want to check the module investigation exercise here. You should now have a working executable. Try to run:

./hello_world.x

Type make again. What happens now?

Open Makefile_2 and have a look. What is different compared to Makefile?

Do a clean up of the build directory:

rm hello_world.x
rm hello_world.o

Build the executable using Makefile_2

make -f Makefile_2

And use Makefile_2 to clean the build directory

make -f Makefile_2 clean

Open Makefile_3 and have a look. What is different this time? Compile hello_world using Makefile_3.

In the folder compile you will also find hello_nc_world.f90. What is the difference between hello_world.f90 and hello_nc_world.f90?

Rewrite the instruction in Makfile_3 so that it compiles hello_nc_world instead of hello_world and compile. What happens?

We need a netCDF library. Check if that is available:

module avail netcdf

Load a netCDF module that is compatible with the compiler that you have chosen. Revise the module exercise again.

Open Makefile_nc and compare to Makefile_3. What is different?

Compile hello_nc_world using Makefile_nc:

make -f Makefile_nc

Run the executable. What was the result?