| CMP0155 | |
| ------- | |
| .. versionadded:: 3.28 | |
| C++ sources in targets with at least C++20 are scanned for imports | |
| when supported. | |
| CMake 3.27 and below assume that C++ sources do not ``import`` modules. | |
| CMake 3.28 and above prefer to assume that C++ sources in targets using C++20 | |
| or higher might ``import`` modules, and must be scanned before compiling, | |
| unless explicitly disabled. This policy provides compatibility for projects | |
| that use C++20 or higher, without modules, that have not been updated to turn | |
| off scanning, e.g., via the :variable:`CMAKE_CXX_SCAN_FOR_MODULES` variable. | |
| See the :manual:`cmake-cxxmodules(7)` manual for more details on C++ module | |
| support. | |
| The ``OLD`` behavior for this policy is to assume that C++ 20 and newer | |
| sources do not import modules. The ``NEW`` behavior for this policy is to | |
| assume that C++ 20 and newer files may import modules if the compiler | |
| understands how to scan for their dependencies, and need to be scanned. | |
| .. |INTRODUCED_IN_CMAKE_VERSION| replace:: 3.28 | |
| .. |WARNS_OR_DOES_NOT_WARN| replace:: does *not* warn | |
| .. include:: include/STANDARD_ADVICE.rst | |
| .. include:: include/DEPRECATED.rst |