判断操作系统
IF (CMAKE_SYSTEM_NAME MATCHES "Linux")
ELSEIF (CMAKE_SYSTEM_NAME MATCHES "Windows")
ELSEIF (CMAKE_SYSTEM_NAME MATCHES "FreeBSD")
ELSE ()
MESSAGE(STATUS "other platform: ${CMAKE_SYSTEM_NAME}")
ENDIF (CMAKE_SYSTEM_NAME MATCHES "Linux")
判断编译器
if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
using Clang
elseif ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
using GCC
elseif ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Intel")
using Intel C++
elseif ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "MSVC")
using Visual Studio C++
endif()