Native build system toolset specification provided by user.

Some CMake generators support a toolset specification to tell the native build system how to choose a compiler. If the user specifies a toolset (e.g. via the cmake(1) -T option or via the CMAKE_GENERATOR_TOOLSET environment variable) the value will be available in this variable.

The value of this variable should never be modified by project code. A toolchain file specified by the CMAKE_TOOLCHAIN_FILE variable may initialize CMAKE_GENERATOR_TOOLSET. Once a given build tree has been initialized with a particular value for this variable, changing the value has undefined behavior.

Toolset specification is supported only on specific generators:

See native build system documentation for allowed toolset names.

Visual Studio Toolset Selection

The Visual Studio Generators support toolset specification using one of these forms:

  • toolset

  • toolset[,key=value]*

  • key=value[,key=value]*

The toolset specifies the toolset name. The selected toolset name is provided in the CMAKE_VS_PLATFORM_TOOLSET variable.

The key=value pairs form a comma-separated list of options to specify generator-specific details of the toolset selection. Supported pairs are:


Specify the CUDA toolkit version to use or the path to a standalone CUDA toolkit directory. Supported by VS 2010 and above. The version can only be used with the CUDA toolkit VS integration globally installed. See the CMAKE_VS_PLATFORM_TOOLSET_CUDA and CMAKE_VS_PLATFORM_TOOLSET_CUDA_CUSTOM_DIR variables.


Specify the host tools architecture as x64 or x86. Supported by VS 2013 and above. See the CMAKE_VS_PLATFORM_TOOLSET_HOST_ARCHITECTURE variable.


Specify the toolset version to use. Supported by VS 2017 and above with the specified toolset installed. See the CMAKE_VS_PLATFORM_TOOLSET_VERSION variable.


Specify an alternative VCTargetsPath value for Visual Studio project files. This allows use of VS platform extension configuration files (.props and .targets) that are not installed with VS.