What are makefile dependencies and how do I use them?

What are makefile dependencies and how do I use them?

Makefile dependencies define relationships between files in a project. They specify which files need to be rebuilt when a source file changes.

Can you give me an example of how to set up dependencies in a makefile?

Sure! Here's a simple example:

all: main.o utils.o

main.o: main.c utils.h
	gcc -c main.c

utils.o: utils.c utils.h
	gcc -c utils.c

What happens if I don't specify dependencies?

If you don't specify dependencies, make won't know which files need to be rebuilt, potentially leading to outdated binaries.

How can I check if my makefile is working correctly?

You can run make -n to see what would be done without actually executing the commands. This helps verify your dependencies.