Given a CMakeLists file, is there any way to know which parent CMakeLists 'called' it?

Question

Given a big cmake project, let B be a CMakeLists.txt, located at some directory within it. Is there any way to print (message(...)) from within B which parent CMakeLists.txt file did the add_subdirectory(B) or equivalent?

Note: Let's suppose that no cmake files do literally add_subdirectory(B), but rather add_subdirectory(${X}), being X the path to subdirectory B, determined through the cmake tree somehow. Otherwise, this could be determined just with grep.

score 2 · Accepted Answer · answered Sep 14 '20 at 13:35

2

Property PARENT_DIRECTORY contains parent source directory:

get_directory_property(parent_dir PARENT_DIRECTORY)
if (parent_dir)
    message(STATUS "I am called with 'add_subdirectory' from script ${parent_dir}/CMakeLists.txt")
else ()
    message(STATUS "I am top-level CMakeLists.txt script)
endif()

See also How to detect if current scope has a parent in CMake?

answered Sep 14 '20 at 13:35

Tsyvarev

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1

If the child CMake file was added via `include()` or `find_package()`, the `PARENT_DIRECTORY` property will also return empty string. So for these cases, you can instead use [`CMAKE_PARENT_LIST_FILE`](https://cmake.org/cmake/help/v3.18/variable/CMAKE_PARENT_LIST_FILE.html) to obtain the full path to the parent CMakeLists.txt file. – Kevin Sep 14 '20 at 13:42
Yes, `PARENT_DIRECTORY` works only for inclusion via `add_subdirectory()`. And `CMAKE_PARENT_LIST_FILE` works only for inclusions via `include()` and `find_package()`. – Tsyvarev Sep 14 '20 at 13:46

Given a CMakeLists file, is there any way to know which parent CMakeLists 'called' it?

1 Answers1