The export-* tests here might have a simple case to look at. If something more complicated confuses things, let’s figure out where it breaks down.
I attached a small producer + consumer pair of projects to the following issue recently. It may serve to show you how to do things.
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:
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.
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)?
FWIW, this test 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.
I’ve made a reproducer case; tracking it down.
Sorry for the delay, Ben!
Here’s a minimal example within what I interacted with the problem: GitHub - 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.
Thanks for the test cases. I tested it with 3.29.0-rc2 and things worked (after making changes to install to $PWD/install and use m gcc build instead).
I have tested it with clang-17 on OSX too, but the error occurs:
bash-5.2$ 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$
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
But on my OSX, I get an error.
snipped of module_libConfig.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 "${_IMPORT_PREFIX}/include"
INTERFACE_LINK_LIBRARIES "GTest::gtest"
)
IMHO: find_dependency(Gtest) is missing too!
The error occurs, if GTest is installed to /opt or /usr/local which are not in default include path!
CMake doesn’t generate anything like that today; you’ll need to provide that call.
But I added it, only it does not help:
include(CMakeFindDependencyMacro)
find_dependency(GTest 1.14 CONFIG REQUIRED)
include("${CMAKE_CURRENT_LIST_DIR}/@PROJECT_NAME@Targets.cmake")
@ben.boeckel It does still not work on OSX. What is different on Apple?
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$
I’ve aso tested it with 3.29.0-rc2 and it worked, thanks!
On OSX too:
bash-5.2$ /Applications/CMake.app/Contents/bin/cmake --version
cmake version 3.29.0-rc2
CMake suite maintained and supported by Kitware (kitware.com/cmake).
bash-5.2$ time ninja
[7/7] Linking CXX executable /Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/module-exe/bin/test_main
real 0m2.869s
user 0m2.543s
sys 0m0.309s
bash-5.2$ bash-5.2$ ctest
Test project /Users/clausklein/Workspace/cpp/cxx20/cmake-module-error/build/module-exe
Start 1: test_main
1/1 Test #1: test_main ........................ Passed 0.10 sec
100% tests passed, 0 tests failed out of 1
Total Test time (real) = 0.11 sec
bash-5.2$
3.28.4 will include the fix.
1 Like