I'm trying to get the inline package working on my macbook. The following block of code (from the cxxfunction examples) fails: library(inline) fx <- cxxfunction( signature(x = "integer", y = "numeric" ) , ' return ScalarReal( INTEGER(x)[0] * REAL(y)[0] ) ; ' ) fx( 2L, 5 ) With this error: Error in compileCode(f, code, language = language, verbose = verbose) : Compilation ERROR, function(s)/method(