Swift_SEPARATE_MODULE_EMISSION

Added in version 4.4.

Emit Swift modules separately from compilation in the Ninja Generators.

When this property is set to ON on an importable Swift target built by Ninja Generators, CMake emits a separate -emit-module build edge that produces the .swiftmodule independently of object compilation. This allows downstream Swift targets to begin compiling as soon as the module interface is available, rather than waiting for all upstream compilation outputs.

The property is initialized from the value of the CMAKE_Swift_SEPARATE_MODULE_EMISSION variable, if it is set. If this property is not set, separate module emission is enabled by default. See policy CMP0215.

Note

Separate module emission takes effect only when policy CMP0157 is set to NEW prior to the first project() or enable_language() command that enables the Swift language.