Cmake package not found

Question

I've installed Drogon using vcpkg, and in my IDE I have following error: Package 'Drogon' not found. After installing, regenerate the CMake cache.

I am using Visual Studio 2022

vcpkg_rf.txt:

install
drogon

CMakeLists.txt:

# CMakeList.txt : Top-level CMake project file, do global configuration
# and include sub-projects here.
#
cmake_minimum_required (VERSION 3.8)

project ("Drogon Server1")

# Include sub-projects.
add_subdirectory ("Drogon Server1")

# Line below is showing the error
find_package(Drogon CONFIG REQUIRED)
target_link_libraries("Drogon Server1" PRIVATE Drogon::Drogon)

I have found this error also:

CMake Error at C:/Users/MY_USERNAME/Documents/sdk/vcpkg/scripts/buildsystems/vcpkg.cmake:829 (_find_package):
  Could not find a package configuration file provided by "Drogon" with any
  of the following names:

    DrogonConfig.cmake
    drogon-config.cmake

  Add the installation prefix of "Drogon" to CMAKE_PREFIX_PATH or set
  "Drogon_DIR" to a directory containing one of the above files.  If "Drogon"
  provides a separate development package or SDK, be sure it has been
  installed.

Did you use the vcpkg toolchain file when you configured your package on the command line? Or are you using a CMakeSettings.json file configured with the toolchain: [https://vcpkg.readthedocs.io/en/latest/examples/installing-and-using-packages/](https://vcpkg.readthedocs.io/en/latest/examples/installing-and-using-packages/) — drescherjm, Aug 26 '22 at 13:01
like this: `"CMAKE_TOOLCHAIN_FILE": "C:/Users/MY_USERNAME/Documents/sdk/vcpkg/scripts/buildsystems/vcpkg.cmake"` — Penny M., Aug 26 '22 at 13:07
I do have a complaint `project ("Drogon Server1")` and `add_subdirectory ("Drogon Server1")` you should avoid spaces in both of these. — drescherjm, Aug 26 '22 at 13:22
Is there more info in the error message? I use vcpkg + Visual Studio + CMake but don't use the integration in the IDE. I use the standalone CMake-GUI to configure and generate my VS project. In CMake-GUI it should give you a longer error message when it cant find a package. It should mention that there are 2 files that it searched for but did not find and give the file names. If you see that check if either of these exist. — drescherjm, Aug 26 '22 at 13:29
Assuming you create the target `"Drogon Server1"` in your `add_subdirectory` CMakeLists.txt you need to properly enclose it in quotes in your `target_link_libraries` command. Try to avoid spaces in target names! — vre, Aug 26 '22 at 13:35
@vre I added quotes around it and it still gives me this error. (I have done this: `target_link_libraries("Drogon Server1" PRIVATE Drogon::Drogon)`) — Penny M., Aug 26 '22 at 13:38
@drescherjm I have added error it gives me at the end of question — Penny M., Aug 26 '22 at 13:41
Does your directory `C:/Users/MY_USERNAME/Documents/sdk/vcpkg` contains any Drogon files? `dir /r /s Drogon*` should show the files. — vre, Aug 26 '22 at 13:44
@vre Yes it does, it is saying: `Total files listed: 57 File(s)` — Penny M., Aug 26 '22 at 13:49
And are those `.cmake` files in question amongst them? How are they named? — vre, Aug 26 '22 at 13:56
@vre I can see some: `DrogonUtilities.cmake`, `DrogonConfig.cmake.in`, `DrogonConfigVersion.cmake`, `DrogonConfig.cmake`, `DrogonTargets.cmake`, `DrogonTargets-debug.cmake`, `DrogonTargets.cmake`, `DrogonTargets-release.cmake`, ... — Penny M., Aug 26 '22 at 13:59
Did you cleared the CMake cache as suggested, i.e. deleted CMakeCache.txt and CMakeFiles in the build directory or started in a fresh build directory after installation of drogon? — vre, Aug 26 '22 at 14:06
@vre I did, I have deleted whole build directory, I have even created another CMake project without spaces in the name, and it is still showing this error — Penny M., Aug 26 '22 at 14:11
There should be an entry in your CMakePresets.json file named `cacheVariables`. Please add a variable `Drogon_DIR` to it with the path to the `DrogonConfig.cmake` file, e.g. `"cacheVariables": { "Drogon_DIR": "" },` and retry in a new builddir — vre, Aug 26 '22 at 14:18

score 1 · Accepted Answer · answered Sep 13 '22 at 10:23

Considering the given information:

Visual Studio 2022

-> Means CMake will default to x64 -> vcpkg will use VCPKG_TARGET_TRIPLET=x64-windows

vcpkg_rf.txt: install drogon

-> Means you use a response file to install drogon. Without specifying the triplet this is x86-windows

As such your triplet used by CMake and vcpkg doesn't agree. Consider using vcpkg in manifest mode by providing a vcpkg.json with the dependency instead of a response file. This way you won't have a discrepancy in your triplet selection

(As always chanigng this also requires to delete the cmake cache for a clean reconfigure. Furthermore don't have spaces in your target and paths; you are just asking for trouble.)

Cmake package not found

1 Answers1