CMP0197 — CMake 4.2.6 Documentation

# CMP0197

Added in version 4.1.

MSVC link `-machine:` flag is not in `CMAKE_*_LINKER_FLAGS`.

When using MSVC-like compilers in CMake 4.0 and below, the linker's `-machine:` flag is added via language-agnostic linker flag variables:

- `CMAKE_EXE_LINKER_FLAGS`

- `CMAKE_SHARED_LINKER_FLAGS`

- `CMAKE_MODULE_LINKER_FLAGS`

- `CMAKE_STATIC_LINKER_FLAGS`

This is problematic when multiple languages' toolchains disagree about if/how to pass the flag through a compiler driver to the linker. Furthermore, carrying the flag in public-facing variables allows projects or users to change it even though it is required.

CMake 4.1 and above prefer to leave the `-machine:` flag out of `CMAKE_*_LINKER_FLAGS` variables, and instead generate the link flag automatically where needed.

This policy provides compatibility with projects that have not been updated to expect the lack of the `-machine:` flags. The policy setting takes effect as of the first `project()` or `enable_language()` command that initializes the above-listed `CMAKE_*_LINKER_FLAGS` variables.

Note

Once the policy has taken effect at the top of a project for a given language, that choice must be used throughout the tree for that language. In projects that have nested projects in subdirectories, be sure to convert everything together.

The `OLD` behavior for this policy is to place the MSVC `-machine:` flag in `CMAKE_*_LINKER_FLAGS`. The `NEW` behavior for this policy is to not place the MSVC `-machine:` flag in `CMAKE_*_LINKER_FLAGS`.

This policy was introduced in CMake version 4.1. It may be set by `cmake_policy()` or `cmake_minimum_required()`. If it is not set, CMake does not warn, and uses `OLD` behavior.

Note

The `OLD` behavior of a policy is `deprecated by definition` and may be removed in a future version of CMake.