I just cleaned up my home brew cellar and had problems reinstalling R. I got the old well-known error message: brew install r ==> Downloading http://cran.r-project.org/src/base/R-2/R-2.15.1.tar.gz Already downloaded: /Library/Caches/Homebrew/r-2.15.1.tar.gz Error: This formula requires a fortran compiler,... Reinstalling gfortran (which was actually installed already) did not help and so I decided to trick home brew until the problem is fixed, with the following: export FC=`which gfortran` brew install r Surprise surprise, it worked! :] ...

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