According to https://gitlab.kitware.com/cmake/cmake/-/issues/17976,
CMAKE_VS_PLATFORM_TOOLSET is set only when using a Visual Studio generator.
When we use Ninja as the generator, CMAKE_VS_PLATFORM_TOOLSET will be empty.
As a result:
if(${CMAKE_VS_PLATFORM_TOOLSET} STREQUAL "v140")
will be treated as:
if( STREQUAL "v140")
We may also quote it like this:
if("${CMAKE_VS_PLATFORM_TOOLSET}" STREQUAL "v140")
but that won't make the warnings disappeared in VS2015.
Daniel Lemire
myd7349
Daniel Lemire
John Keiser