# Installed module library can't find imported headers \[Ubuntu 22.04 LTS, CMake 3.28.1, Ninja 1.11.1 and Clang 17.0.6\]

**URL:** https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819
**Category:** Usage
**Tags:** os:linux, comp:clang, gen:ninja, tool:cmake
**Created:** [January 11, 2024, 12:03am UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819 "2024-01-11T00:03:05Z")
**Posts on this page:** 20
**Page:** 1

<div class="post-metadata">

### Author: ![josecruz](https://discourse.cmake.org/user_avatar/discourse.cmake.org/josecruz/32/2342_2.png) [@josecruz](https://discourse.cmake.org/u/josecruz)
#### Post date: [January 11, 2024, 12:03am UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/1 "2024-01-11T00:03:05Z")

</div>

Using Ubuntu 22.04 LTS, CMake 3.28.1, Ninja 1.11.1 and Clang 17.0.6, I’m trying to create a library using modules, supported under these conditions, as described at import-cmake-the-experiment-is-over.

I managed to successfully create a library with modules, and link it to an executable in the same project.

–

My library is quite simple:

```cpp

// robocin/utility/concepts.ixx

module;

#include <concepts>

#include <google/protobuf/message_lite.h>

export module robocin.utility:concepts;

export namespace robocin {

template <class T>

concept protobufish = std::derived_from<std::remove_cvref_t<T>, ::google::protobuf::MessageLite>;

} // namespace robocin

```

```cpp

// robocin/utility/utility.ixx

export module robocin.utility;

export import :concepts;

```

- [Here](https://pastebin.com/91kLYt6p) is my rule responsible for creating a library.

```CMake
// CMakeLists.txt

robocin_cpp_library(
  NAME utility
  MODS utility.ixx
  concepts.ixx
  DEPS protobuf::libprotobuf
)

robocin_cpp_executable(
  NAME local_target
  SRCS local_target_main.cpp
  DEPS utility
)

```

```cpp

// robocin/utility/local_target_main.cpp

#include <iostream>
#include <vector>

import robocin.utility;

int main() { return robocin::protobufish<std::vector<int>>; }

```

Compile and works as expected.

–

However, when I tried to install it and use it in an executable in another project, the library created with modules was unable to find the included dependency:

```CMake
// CMakeLists.txt

robocin_cpp_executable(
  NAME external_target
  SRCS external_target_main.cpp
  DEPS common::utility # utility library generated by robocin/utility project and installed on the system.
)

```

```cpp

// experimental/external_target_main.cpp (same as robocin/utility/local_target_main.cpp)

#include <iostream>
#include <vector>

import robocin.utility;

int main() { return robocin::protobufish<std::vector<int>>; }

```

Compiling output:

```bash

[proc] Executing command: /usr/local/bin/cmake --build /workspaces/project/experiments/cpp-modules/build --config Debug --target all -j 6 --

[build] [1/6 16% :: 0.058] Scanning /usr/local/modules/concepts.ixx for CXX dependencies

[build] FAILED: CMakeFiles/common__utility@synth_ee677d4352ba.dir/90ece7fad90b.bmi.ddi

[build] "/usr/bin/clang-scan-deps-17" -format=p1689 -- /usr/bin/clang++ -DROBOCIN_PROJECT_NAME=\"common\" -DROBOCIN_PROJECT_PATH=\"/tmp/common/cpp\" -I/tmp/common/cpp -I/tmp/common/cpp/build -g -std=gnu++23 --precompile -x c++ /usr/local/modules/concepts.ixx -c -o CMakeFiles/common __utility@synth_ee677d4352ba.dir/90ece7fad90b.bmi -MT CMakeFiles/common__ utility@synth_ee677d4352ba.dir/90ece7fad90b.bmi.ddi -MD -MF CMakeFiles/common __utility@synth_ee677d4352ba.dir/90ece7fad90b.bmi.ddi.d > CMakeFiles/common__ utility@synth_ee677d4352ba.dir/90ece7fad90b.bmi.ddi.tmp && mv CMakeFiles/common __utility@synth_ee677d4352ba.dir/90ece7fad90b.bmi.ddi.tmp CMakeFiles/common__ utility@synth_ee677d4352ba.dir/90ece7fad90b.bmi.ddi

[build] Error while scanning dependencies for /usr/local/modules/concepts.ixx:

[build] /usr/local/modules/concepts.ixx:4:10: fatal error: 'google/protobuf/message_lite.h' file not found

[build] ninja: build stopped: subcommand failed.

```

- [Here](https://pastebin.com/bTnwM33C) is the generated CMake file, which I imagine is imported by the executable for linking dependencies.

Previously this same library was a header, and it worked in both cases.

A complete example with all the files is available on GitHub: robocin/ssl-core/tree/cpp-modules.

---

<div class="post-metadata">

### Author: ![ben.boeckel](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [January 18, 2024, 11:37pm UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/2 "2024-01-18T23:37:59Z")

</div>

Thanks for the report; I don’t have time to dig into it right now, but I added it to my “C++ modules” task pile when I get the chance.

---

<div class="post-metadata">

### Author: ![josecruz](https://discourse.cmake.org/user_avatar/discourse.cmake.org/josecruz/32/2342_2.png) [@josecruz](https://discourse.cmake.org/u/josecruz)
#### Post date: [January 19, 2024, 1:24am UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/3 "2024-01-19T01:24:28Z")

</div>

Thanks @ben.boeckel! Something that could also help would be to have a practical example of an installable C++ module library that uses third parties/external dependencies, which is exactly my problem. I can try to understand the error better from a functional example, and if I find the solution, I can clarify the error here to help anyone else who faces the same problem in the future.

As it’s something new, I couldn’t find any examples in this direction.

---

<div class="post-metadata">

### Author: ![ben.boeckel](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [January 19, 2024, 5:32am UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/4 "2024-01-19T05:32:22Z")

</div>

The `export-*` tests [here](https://gitlab.kitware.com/cmake/cmake/-/tree/master/Tests/RunCMake/CXXModules/examples) might have a simple case to look at. If something more complicated confuses things, let’s figure out where it breaks down.

---

<div class="post-metadata">

### Author: ![craig.scott](https://discourse.cmake.org/user_avatar/discourse.cmake.org/craig.scott/32/20_2.png) [@craig.scott](https://discourse.cmake.org/u/craig.scott)
#### Post date: [January 19, 2024, 7:58am UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/5 "2024-01-19T07:58:48Z")

</div>

I attached a small producer + consumer pair of projects to the following issue recently. It may serve to show you how to do things.

[https://gitlab.kitware.com/cmake/cmake/-/issues/25594](https://gitlab.kitware.com/cmake/cmake/-/issues/25594)

---

<div class="post-metadata">

### Author: ![josecruz](https://discourse.cmake.org/user_avatar/discourse.cmake.org/josecruz/32/2342_2.png) [@josecruz](https://discourse.cmake.org/u/josecruz)
#### Post date: [January 21, 2024, 9:14pm UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/6 "2024-01-21T21:14:19Z")

</div>

I looked at the links you pointed out and ended up making some adjustments to my rules because of this, but they didn’t solve the problem I reported.

However, I noticed that when I added the path of the third party libraries to this `IMPORTED_CXX_MODULES_INCLUDE_DIRECTORIES` variable in the auto-generated CMake file, the compilation worked normally.

Trying to figure out how to make it work, I realized that I had to add:

```CMake
foreach (DEP ${DEPENDENCIES})
  get_target_property(dep_include_dirs ${DEP} INTERFACE_INCLUDE_DIRECTORIES)
  target_include_directories(${LIBRARY_NAME} PRIVATE ${dep_include_dirs})
endforeach ()

```

Which I didn’t need before for my headers library 🤔.

Now it seems to work normally.

---

<div class="post-metadata">

### Author: ![ben.boeckel](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [January 22, 2024, 2:53pm UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/7 "2024-01-22T14:53:37Z")

</div>

Do you link to targets for your dependencies? Can you try to boil this down to a minimal example that I can investigate (assuming it is not covered by Craig’s 25594 example)?

---

<div class="post-metadata">

### Author: ![ben.boeckel](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [February 16, 2024, 2:07pm UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/8 "2024-02-16T14:07:33Z")

</div>

@josecruz Any update on a minimal reproducer?

---

<div class="post-metadata">

### Author: ![ben.boeckel](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [February 16, 2024, 3:18pm UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/9 "2024-02-16T15:18:08Z")

</div>

FWIW, [this test](https://gitlab.kitware.com/cmake/cmake/-/tree/master/Tests/RunCMake/CXXModules/examples/export-include-directories-build) shows that includes work, but it is its own provided headers. I’ll try to see about adding a test that transitive dependencies get propagated properly.

---

<div class="post-metadata">

### Author: ![ben.boeckel](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [February 16, 2024, 6:41pm UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/10 "2024-02-16T18:41:14Z")

</div>

I’ve made a reproducer case; tracking it down.

---

<div class="post-metadata">

### Author: ![ben.boeckel](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [February 16, 2024, 10:28pm UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/11 "2024-02-16T22:28:02Z")

</div>

Fix is here: [https://gitlab.kitware.com/cmake/cmake/-/merge\_requests/9265](https://gitlab.kitware.com/cmake/cmake/-/merge_requests/9265)

---

<div class="post-metadata">

### Author: ![josecruz](https://discourse.cmake.org/user_avatar/discourse.cmake.org/josecruz/32/2342_2.png) [@josecruz](https://discourse.cmake.org/u/josecruz)
#### Post date: [February 18, 2024, 7:20pm UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/12 "2024-02-18T19:20:27Z")

</div>

Sorry for the delay, Ben!

Here’s a minimal example within what I interacted with the problem: [GitHub - joseviccruz/cmake-module-error](https://github.com/joseviccruz/cmake-module-error)

In this test I use the GoogleTest library, installed in the `/opt` directory.

The three root scripts execute the installation of a simple library with a header or module in `/usr/local` and then try to execute that library in another project.

---

<div class="post-metadata">

### Author: ![ben.boeckel](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [February 23, 2024, 4:57am UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/13 "2024-02-23T04:57:23Z")

</div>

Thanks for the test cases. I tested it with 3.29.0-rc2 and things worked (after making changes to install to `$PWD/install` and use m gcc build instead).

---

<div class="post-metadata">

### Author: ![ClausKlein](https://discourse.cmake.org/user_avatar/discourse.cmake.org/clausklein/32/352_2.png) [@ClausKlein](https://discourse.cmake.org/u/ClausKlein)
#### Post date: [February 24, 2024, 3:03pm UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/14 "2024-02-24T15:03:58Z")

</div>

I have tested it with clang-17 on OSX too, but the error occurs:

```bash
bash-5.2$ gmake -n 
cd module-lib && cmake --workflow --preset default --fresh && cmake --build --preset default --target install
cd module-exe && cmake --workflow --preset default --fresh && cmake --build --preset default --target test
cd header-lib && cmake --workflow --preset default --fresh && cmake --build --preset default --target install
cd header-exe && cmake --workflow --preset default --fresh && cmake --build --preset default --target test
TEST_FORCING_MODULE_ERROR=ON gmake working
gmake[1]: Entering directory '/Users/clausklein/Workspace/cpp/cxx20/cmake-module-error'
cd module-lib && cmake --workflow --preset default --fresh && cmake --build --preset default --target install
cd module-exe && cmake --workflow --preset default --fresh && cmake --build --preset default --target test
gmake[1]: Leaving directory '/Users/clausklein/Workspace/cpp/cxx20/cmake-module-error'
bash-5.2$ 
bash-5.2$ make clean
rm -rf build stagedir
bash-5.2$ gmake failing
TEST_FORCING_MODULE_ERROR=ON gmake working
gmake[1]: Entering directory '/Users/clausklein/Workspace/cpp/cxx20/cmake-module-error'
cd module-lib && cmake --workflow --preset default --fresh && cmake --build --preset default --target install
Executing workflow step 1 of 2: configure preset "default"

Preset CMake variables:

  BUILD_SHARED_LIBS="NO"
  CMAKE_BUILD_TYPE="Release"
  CMAKE_CXX_SCAN_FOR_MODULES:BOOL="TRUE"
  CMAKE_CXX_STANDARD="23"
  CMAKE_INSTALL_PREFIX:PATH="/Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/stagedir"
  CMAKE_PREFIX_PATH:STRING="/Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/stagedir"
  TEST_FORCING_MODULE_ERROR="ON"

Preset environment variables:

  CPM_USE_LOCAL_PACKAGES="NO"
  PATH="/Users/clausklein/.local/bin:/usr/local/opt/llvm/bin://Users/clausklein/perl5/bin:/usr/local/opt/net-snmp/bin:/usr/local/opt/coreutils/libexec/gnubin:/usr/local/libexec/bin:/usr/local/opt/curl/bin:/usr/local/opt/libxml2/bin:/usr/local/opt/libxslt/bin:/usr/local/opt/expat/bin:/usr/local/opt/net-snmp/bin:/Users/clausklein/Library/Python/3.9/bin:/usr/local/opt/python/libexec/bin:/usr/local/opt/sqlite/bin:/usr/local/bin:/usr/local/sbin:/Users/clausklein/scripts:/Users/clausklein/bin:/usr/local/bin:/System/Cryptexes/App/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/local/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/appleinternal/bin:/opt/X11/bin:/Library/Apple/usr/bin:/usr/local/MacGPG2/bin:/usr/texbin"

-- The CXX compiler identification is Clang 17.0.6
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /usr/local/opt/llvm/bin/clang++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD - Success
-- Found Threads: TRUE  
-- Using GTest: 1.14.0
CMake Warning at /Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/helpers.cmake:108 (message):
  TEST_FORCING_MODULE_ERROR
Call Stack (most recent call first):
  test-library/CMakeLists.txt:1 (robocin_cpp_library)

-- Configuring done (1.9s)
-- Generating done (0.0s)
-- Build files have been written to: /Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/build/module-lib

Executing workflow step 2 of 2: build preset "default"

[4/4] Linking CXX static library test-library/libtest_class.a
[0/1] Install the project...
-- Install configuration: "Release"
-- Installing: /Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/stagedir/include/test-library/test_class.ixx
-- Installing: /Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/stagedir/lib/libtest_class.a
-- Installing: /Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/stagedir/modules/test_class.ixx
-- Installing: /Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/stagedir/modules/test.pcm
-- Installing: /Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/stagedir/lib/cmake/module_lib/module_libConfig.cmake
-- Installing: /Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/stagedir/lib/cmake/module_lib/module_libConfig-release.cmake
-- Installing: /Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/stagedir/lib/cmake/module_lib/cxx_modules/cxx-modules-module_libTargets.cmake
-- Installing: /Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/stagedir/lib/cmake/module_lib/cxx_modules/cxx-modules-module_libTargets-Release.cmake
-- Installing: /Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/stagedir/lib/cmake/module_lib/cxx_modules/target-test_class-Release.cmake
cd module-exe && cmake --workflow --preset default --fresh && cmake --build --preset default --target test
Executing workflow step 1 of 2: configure preset "default"

Preset CMake variables:

  BUILD_SHARED_LIBS="NO"
  CMAKE_BUILD_TYPE="Release"
  CMAKE_CXX_SCAN_FOR_MODULES:BOOL="TRUE"
  CMAKE_CXX_STANDARD="23"
  CMAKE_INSTALL_PREFIX:PATH="/Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/stagedir"
  CMAKE_PREFIX_PATH:STRING="/Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/stagedir"
  TEST_FORCING_MODULE_ERROR="ON"

Preset environment variables:

  CPM_USE_LOCAL_PACKAGES="NO"
  PATH="/Users/clausklein/.local/bin:/usr/local/opt/llvm/bin://Users/clausklein/perl5/bin:/usr/local/opt/net-snmp/bin:/usr/local/opt/coreutils/libexec/gnubin:/usr/local/libexec/bin:/usr/local/opt/curl/bin:/usr/local/opt/libxml2/bin:/usr/local/opt/libxslt/bin:/usr/local/opt/expat/bin:/usr/local/opt/net-snmp/bin:/Users/clausklein/Library/Python/3.9/bin:/usr/local/opt/python/libexec/bin:/usr/local/opt/sqlite/bin:/usr/local/bin:/usr/local/sbin:/Users/clausklein/scripts:/Users/clausklein/bin:/usr/local/bin:/System/Cryptexes/App/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/local/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/appleinternal/bin:/opt/X11/bin:/Library/Apple/usr/bin:/usr/local/MacGPG2/bin:/usr/texbin"

-- The CXX compiler identification is Clang 17.0.6
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /usr/local/opt/llvm/bin/clang++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD - Success
-- Found Threads: TRUE  
-- Using GTest: 1.14.0
-- Using module_lib: '/Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/stagedir/lib/cmake/module_lib'
-- Configuring done (2.0s)
-- Generating done (0.0s)
CMake Warning:
  Manually-specified variables were not used by the project:

    TEST_FORCING_MODULE_ERROR

-- Build files have been written to: /Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/build/module-exe

Executing workflow step 2 of 2: build preset "default"

[1/6] Scanning /Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/stagedir/modules/test_class.ixx for CXX dependencies
FAILED: CMakeFiles/module_lib__test_class@synth_800cc612d0fe.dir/9ece086e9bac.bmi.ddi 
"/usr/local/Cellar/llvm/17.0.6_1/bin/clang-scan-deps" -format=p1689 -- /usr/local/opt/llvm/bin/clang++ -DPROJECT_PATH=\"/Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/module-lib\" -I/Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/module-lib -I/Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/build/module-lib -O3 -DNDEBUG -std=gnu++23 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX14.2.sdk --precompile -x c++ /Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/stagedir/modules/test_class.ixx -c -o CMakeFiles/module_lib __test_class@synth_800cc612d0fe.dir/9ece086e9bac.bmi -MT CMakeFiles/module_lib__ test_class@synth_800cc612d0fe.dir/9ece086e9bac.bmi.ddi -MD -MF CMakeFiles/module_lib __test_class@synth_800cc612d0fe.dir/9ece086e9bac.bmi.ddi.d > CMakeFiles/module_lib__ test_class@synth_800cc612d0fe.dir/9ece086e9bac.bmi.ddi.tmp && mv CMakeFiles/module_lib __test_class@synth_800cc612d0fe.dir/9ece086e9bac.bmi.ddi.tmp CMakeFiles/module_lib__ test_class@synth_800cc612d0fe.dir/9ece086e9bac.bmi.ddi
Error while scanning dependencies for /Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/stagedir/modules/test_class.ixx:
/Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/stagedir/modules/test_class.ixx:3:10: fatal error: 'gtest/gtest.h' file not found
ninja: build stopped: subcommand failed.
gmake[1]: *** [GNUmakefile:5: working] Error 1
gmake[1]: Leaving directory '/Users/clausklein/Workspace/cpp/cxx20/cmake-module-error'
gmake: *** [GNUmakefile:8: failing] Error 2
bash-5.2$ 

```

---

<div class="post-metadata">

### Author: ![ClausKlein](https://discourse.cmake.org/user_avatar/discourse.cmake.org/clausklein/32/352_2.png) [@ClausKlein](https://discourse.cmake.org/u/ClausKlein)
#### Post date: [February 24, 2024, 3:08pm UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/15 "2024-02-24T15:08:37Z")

</div>

I have tested it on CI with ubuntu 22.04 and it works?  
see [Use setup-cpp to speeup docker build · ClausKlein/cmake-module-error@5d74595 · GitHub](https://github.com/ClausKlein/cmake-module-error/actions/runs/8029233880/job/21935293142#step:3:3959)

But on my OSX, I get an error.

---

<div class="post-metadata">

### Author: ![ClausKlein](https://discourse.cmake.org/user_avatar/discourse.cmake.org/clausklein/32/352_2.png) [@ClausKlein](https://discourse.cmake.org/u/ClausKlein)
#### Post date: [February 24, 2024, 3:26pm UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/16 "2024-02-24T15:26:04Z")

</div>

snipped of **module\_libConfig.cmake**

```cmake
# Create imported target module_lib::test_class
add_library(module_lib::test_class STATIC IMPORTED)

set_target_properties(module_lib::test_class PROPERTIES
  IMPORTED_CXX_MODULES_COMPILE_DEFINITIONS "PROJECT_PATH=\"/Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/module-lib\""
  IMPORTED_CXX_MODULES_COMPILE_FEATURES "cxx_std_23"
  IMPORTED_CXX_MODULES_INCLUDE_DIRECTORIES "/Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/module-lib;/Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/build/module-lib"
  IMPORTED_CXX_MODULES_LINK_LIBRARIES "\$<COMPILE_ONLY:GTest::gtest>"
  INTERFACE_COMPILE_FEATURES "cxx_std_23"
  INTERFACE_INCLUDE_DIRECTORIES "${_IMPORT_PREFIX}/include"
  INTERFACE_LINK_LIBRARIES "GTest::gtest"
)

```

### IMHO: find\_dependency(Gtest) is missing too!

see [https://github.com/ClausKlein/cmake-module-error/pull/1/commits/5be17a6ea34299f35b2503d4d976094db89be485](https://github.com/ClausKlein/cmake-module-error/pull/1/commits/5be17a6ea34299f35b2503d4d976094db89be485)

---

<div class="post-metadata">

### Author: ![ClausKlein](https://discourse.cmake.org/user_avatar/discourse.cmake.org/clausklein/32/352_2.png) [@ClausKlein](https://discourse.cmake.org/u/ClausKlein)
#### Post date: [February 24, 2024, 5:12pm UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/17 "2024-02-24T17:12:18Z")

</div>

> [@ben.boeckel](#):
>
> Thanks for the test cases. I tested it with 3.29.0-rc2 and things worked (after making changes to install to `$PWD/install` and use m gcc build instead).

The error occurs, if `GTest` is installed to `/opt` or `/usr/local` which are not in default include path!

---

<div class="post-metadata">

### Author: ![ben.boeckel](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [February 24, 2024, 9:08pm UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/18 "2024-02-24T21:08:05Z")

</div>

> [@ClausKlein](#):
>
> IMHO: find\_dependency(Gtest) is missing too!

CMake doesn’t generate anything like that today; you’ll need to provide that call.

---

<div class="post-metadata">

### Author: ![ClausKlein](https://discourse.cmake.org/user_avatar/discourse.cmake.org/clausklein/32/352_2.png) [@ClausKlein](https://discourse.cmake.org/u/ClausKlein)
#### Post date: [February 24, 2024, 9:12pm UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/19 "2024-02-24T21:12:56Z")

</div>

### But I added it, only it does not help:

```cmake
include(CMakeFindDependencyMacro)
find_dependency(GTest 1.14 CONFIG REQUIRED)

include("${CMAKE_CURRENT_LIST_DIR}/@PROJECT_NAME@Targets.cmake")

```

---

<div class="post-metadata">

### Author: ![ClausKlein](https://discourse.cmake.org/user_avatar/discourse.cmake.org/clausklein/32/352_2.png) [@ClausKlein](https://discourse.cmake.org/u/ClausKlein)
#### Post date: [February 24, 2024, 10:10pm UTC](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819/20 "2024-02-24T22:10:24Z")

</div>

@ben.boeckel It does still not work on OSX. What is different on Apple?

```bash
bash-5.2$ find stagedir/include -name gtest.h
stagedir/include/gtest/internal/custom/gtest.h
stagedir/include/gtest/gtest.h

bash-5.2$ ll stagedir/lib/cmake/GTest/*.cmake
-rw-r--r-- 1 clausklein 5.3K Feb 24 22:21 stagedir/lib/cmake/GTest/GTestTargets.cmake
-rw-r--r-- 1 clausklein 2.3K Feb 24 22:21 stagedir/lib/cmake/GTest/GTestTargets-release.cmake
-rw-r--r-- 1 clausklein 1.9K Feb 24 22:21 stagedir/lib/cmake/GTest/GTestConfigVersion.cmake
-rw-r--r-- 1 clausklein 1.1K Feb 24 22:21 stagedir/lib/cmake/GTest/GTestConfig.cmake

bash-5.2$ cmake --version
cmake version 3.28.3
CMake suite maintained and supported by Kitware (kitware.com/cmake).

bash-5.2$ clang --version
Homebrew clang version 17.0.6
Target: x86_64-apple-darwin23.3.0
Thread model: posix
InstalledDir: /usr/local/opt/llvm/bin

bash-5.2$ 

```

[Next page](https://discourse.cmake.org/t/installed-module-library-cant-find-imported-headers-ubuntu-22-04-lts-cmake-3-28-1-ninja-1-11-1-and-clang-17-0-6/9819.md?page=2)