Best practice of c/C++ dependency management on build servers?

Question

I develop largely in java which has maven or ant/ivy. Is there a recommended way to manage build dependencies for c++ projects? I'm setting up the build on our build server right now but the thing that comes to mind is that if the dependency libraries change how do I track that so old builds are not affected but new ones can use newer versions of a library?

One simple thought is that I move all the third party libraries into my repository and then reference them with:

#include "sqlite3.h"
#include "mosquitto.h"

Instead of

#include <sqlite3.h>
#include <mosquitto.h>

Can someone recommend how to best do this in production?

• Alex Reinking: Definitely don't change the code. Moving 3rd party libraries into your repository is fine, but change the include path to accommodate them.
• simgineer: @AlexReinking when you say don't change the code, that means keep the "<sqlite3.h>?
• Alex Reinking: Yes, that's what I mean.
• simgineer: @AlexReinking May I ask how you normally organize third party libraries in a repo? Do you just stick the components into a directory called thirdparty at the root of the repo or is there a more ideal naming convention that is normally used?
• Alex Reinking: If you look at my answer, that's what I suggest. I prefer third_party, but I've also seen thirdparty, Ext, deps, and others.

Answer 1

Moving third party build dependencies into your repository is perfectly fine, and even has some advantages (eg. no version mismatches, tracked upgrades). But doing so should not touch your code.

C/C++ use an include path to determine where to find libraries that are included like so

#include <...>

Depending on your toolchain and build system, you'll have to follow different steps to configure this. Regardless, the best thing would be to create a "third_party" folder with subfolders containing each dependency. Then add each of those folders to your include path such that your existing include directives work.

In CMake, you should use the target_include_directories to accomplish this. In a plain Makefile with GCC or clang, you would add the -I flag for each folder.

• simgineer: If I could inquire just a little more, inside the third_party do you normally place the sqlite.h files at the root of the subdirectories "sqlite3" or "mosquitto" or is there an extra level of directories for "include" and "lib/x86_64-linux-gnu". Seems to me just the first level is sufficient?