What is the proper way to include a source library in a Visual Studio C++ project?

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Right now I'm trying to create my first "real" project in C++ using Visual Studio 2019. I need to include a third-party library as a dependency. The instructions on the project homepage simply recommend to include all source/header files directly into the project. My understanding is that it's a bad practice, since the end result would look quite ugly in any VCS.

Thankfully, the library author also provided build scripts that call cl, lib and link with appropriate arguments and produce the coveted foo.lib. I added that file to dependencies in linker options and after some haranguing with compiler/linker options finally got it running.

To my distress, I realised that I've done all those manipulations in Release configuration, which prevented me from using the debugger. I then built the library with /MDd, fixed some compiler options... and got a bizarre compile-time error in vcruntime.h ( fatal error C1189: #error: _HAS_CXX17 and _HAS_CXX20 must both be defined, and _HAS_CXX20 must imply _HAS_CXX17).

At this point, I knew I was doing something terribly wrong, since including a simple library should't require so much manual knob-tweaking. What is the right, canonical way of including third-party dependencies in Visual Studio (and C++ in general)? Assuming the dependency isn't available on Nuget, vcpkg or somesuch.

visual-studio c++
3 Answers

As I understand from the stuff you did was on Windows. First of all I would recommend you try a linux distro. In windows it is possible to get lib files running, but not easy. It would help if you could send me a link to the library you are using.

user_119508550

The usual approach is to just stick those sources in their own directory and their own Visual Studio project (not solution). This can still build a foo.lib. You won't need many options for this.

Next, you just tell Visual Studio that your own project depends on that other project, and it will then link foo.LIB for you.

Having said that, it sounds like you try to build your two projects with different settings for the C++ version. VS2019 has good support for C++17 and experimental support for C++20, so you can choose. But you need to choose consistently for all your projects.

In larger solutions you can us a .vsprops file for that, which is like an #include for project files. A bit overkill when you have two projects, a lifesaver when you have 150.

MSalters_154160

It varies a bit how you include 3rd party libraries, sometimes 3rd party libraries have an installation and install themselves like under Common Components sometimes you have to do it manually.

E.g. YourSolution/3rdParty/foo/include
     YourSolution/3rdParty/foo/lib 
     YourSolution/3rdParty/foo/lib/release 
     YourSolution/3rdParty/foo/lib/debug

Sometimes the libraries have different names then they may be in the same folder.

Once you have that structure go to your project's properties C/C++ and add the include under Additional Include Directories make sure you have configuration "All Configurations" here. Then go to Project properties/Linker/Input and the dependency for Debug Configuration and for the Release Configuration - since usually they are different libraries per configuration. e.g. release/foo.lib and debug/foo.lib (foo.lib foo-d.lib or whatever they are called).

Use the macros to make sure you get the right locations so that they are relative to your solution and project. It is not good having absolute paths. E.g. $(SolutionDir)3rdparty\foo\include

Disclaimer : I am not sure this is the "optimal" way to do it but that is the way I do it.

user_456850
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