integrating conan with existing cmake project

Question

I want to use conan in an existing CMake project. I have the conanfile.txt in the root directory and run conan install . --build=missing --output-folder=build/conan, but I don't know how to get CMake to find the dependencies it has built/downloaded.

I am using the VSCode CMake extension and it runs this command to generate: /usr/bin/cmake --no-warn-unused-cli -DCMAKE_BUILD_TYPE:STRING=Debug -DCMAKE_EXPORT_COMPILE_COMMANDS:BOOL=TRUE -DCMAKE_C_COMPILER:FILEPATH=/usr/bin/gcc -DCMAKE_CXX_COMPILER:FILEPATH=/usr/bin/g++ -S/home/me/myproject -B/home/me/myproject/build/Debug -G Ninja

conanfile.txt

[requires]
boost/1.85.0
fmt/10.2.1
openssl/3.0.9
cryptopp/8.9.0

[generators]
CMakeDeps

Also, I am using find_package in CMake to find them.

You need to use the CMakeToolchain generator and then use -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake or better the cmake --preset conan-default/conan-release. Also better to use the [layout] with cmake_layout and forget about the --output-folder argument — drodri
– drodri, Commented Jun 3, 2024 at 16:24
You also need to align the dependencies arguments. If you want to build in Debug, then you need to pass the right arguments to conan install, like conan install ... -s build_type=Debug. Likewise, if those compilers are not the default ones in the system (in that case you wouldn't need to define them in command line), better define them in a profile file too, in the [buildenv] section as CC/CXX env-vars, or with [conf] like tools.build:compiler_executables. Check the getting started tutorial: docs.conan.io/2/tutorial/consuming_packages/… — drodri
– drodri, Commented Jun 3, 2024 at 16:26

tkhyn · Accepted Answer · 2025-06-16 07:47:23Z

0

A bit late to the party but it may help people landing on this page with the same issue.

I had a similar problem trying integrate conan 2 into my CMake workflow so wrote a CMake module to invoke (and even install, if needed) conan, possibly depending on CMake options or variables. It is available from https://github.com/tkhyn/cmake-conanfile. It requires a conanfile.py and doesn't work with conanfile.txt but the conversion is easy enough.

edited Jun 16 at 7:47

answered Jun 16 at 7:31

tkhyn

4076 silver badges8 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

integrating conan with existing cmake project

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related