Use if(CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 4.2)
as mentioned by onqtam. This obsolete answer was back from the 2.6 CMake days.
You could run gcc -dumpversion
and parse the output. Here is one way to do that:
if (CMAKE_COMPILER_IS_GNUCC)
execute_process(COMMAND ${CMAKE_C_COMPILER} -dumpversion
OUTPUT_VARIABLE GCC_VERSION)
string(REGEX MATCHALL "[0-9]+" GCC_VERSION_COMPONENTS ${GCC_VERSION})
list(GET GCC_VERSION_COMPONENTS 0 GCC_MAJOR)
list(GET GCC_VERSION_COMPONENTS 1 GCC_MINOR)
message(STATUS ${GCC_MAJOR})
message(STATUS ${GCC_MINOR})
endif()
That would print “4” and “3” for gcc version 4.3.1. However you can use CMake’s version checking syntax to make life a bit easier and skip the regex stuff:
execute_process(COMMAND ${CMAKE_C_COMPILER} -dumpversion
OUTPUT_VARIABLE GCC_VERSION)
if (GCC_VERSION VERSION_GREATER 4.3 OR GCC_VERSION VERSION_EQUAL 4.3)
message(STATUS "Version >= 4.3")
endif()