ubuntu20.04 cmake编译出错:No CMAKE_CXX_COMPILER could be found.
--ThecxxcompileridentificationisunknownCMakeErroratCMakeLists.txt:3(project):NoCMAKE_CXX_COMPILERcouldbefound.TellCNakewheretofindthecompilerbysettingeithertheenvironmentvariable"CXX"ortheCMakecacheen