Makefile-Project-Template

C/C++ Makefile project in VS Code

How to use

VS code config files are not required and will not affect this method(lanuch.json or tasks.json)

To enable debug, in config/make.global: add -g to CFLAGS and CXXFLAGS

Use C/C++ Makefile Project extension to build, run, and debug, VS code default debug is not working.

Original README: Makefile for MEDIUM Project

https://github.com/TheNetAdmin/Makefile-Templates

Introduction

This is the template for MEDIUM Project, which has the features like:

There are nested src folders
There are multiple sub src folders under one src folder
The objects should be held by their folder, rather than a common folder like obj
(Mostly) Only one target to build

All in all, it is possible to write all rules for a medium-size project in the top Makefile, but it's low-efficient and hard to maintain.

How to

When using this template, you may need to:

Copy the top Makefile from Template to your project root folder.
1. Fill the blanks, remove their comments like # FILL: ...
2. NOTE: you should add all the src folders to variable DIRS, and all the objects in the current folder to variable OBJS
Copy the folder config from Template to your project root folder.
1. Specify the compile tool in config/make.global
2. Under Linux/Mac
  1. Delete or comment the line export MAKE := ... in config/make.global
3. Under Windows
  1. Fill the blank of export MAKE := ... and remove it's comment
Create Makefile in each sub src dir, following the template shown in Template/src/Makefile, or Example/.../Makefile

Problem description

Assume we have a project with the following folder structure, we call it a Medium Project

Root: holds the main src file
- Makefile: the top Makefile
- main-src-file
- src-file1
- src1: holds some src dirs and files
  - Makefile: rules to make objects in current dir
  - src-file2
  - src-file3
  - sub-src-dir1: holds some src dirs and files
    - src-file4
    - src-file5
    - Makefile: rules to make objects in current dir
- src2:
  - Makefile: rules to make objects in current dir
  - sub-src-dir2: holds some src dirs and files
    - src-file6
    - src-file7
    - Makefile: rules to make objects in current dir

Work flow

When executing make at the root folder, it will first look into the TARGET file, which depend on all the objects ALL_OBJS specified by the PHONY target find-all-objs.

If any of the objects are not updated, it will be re-generated at its own folder, and TARGET will use it for linking.

When linking, compiler link all the object files under all the src dirs, recursively. Since there are path prefixs, it is ok to have filename conflict in different dir(like having src1/f1.c and src2/f1.c is ok)

FAQs and Discussions

Why we need a Makefile in each src dir
1. This gives us the chance to maintain the objects under their sources' dirs, which further prevent the filename conflict under different path, since the objects will have a path prefix to eliminate the filename conflict.
Why we should manually specify the DIRS and OBJS
1. Just in case some source file are not to be compiled(e.g. a test file named test.c may not need to be compiled), or some dirs does not contain any source files(e.g. a dir doc contains documents), nor in their sub-dirs.
2. It's easy to add some auto-find rules for DIRS and OBJS, using wildcard.
3. For simplicity, we do not provide this kind of auto-find which may cause some trouble unintentionally.
Why use a submake.global, but put all rules in make.global
1. The all and clean rules in sub-dirs is different from the root-dir, these are to specified seperately.
Why re-link and re-generate the target even if all the objects are updated
1. Since the target$(TARGET) depend on some PHONY targets, it may be re-generated even all non-PHONY dependencies are updated. But consider about the simplicity of the Makefile, this redundency is endurable. If anyone has a better idea, feel free to raise an issue or pull-request.

Oct19/Makefile-Project-Template