问题
I'm trying to install Haskell and Yesod for Mac following this guide. Everything goes fine until the last step, when I receive this error message. I've tried to manually install the hfsevebts-0.1.4 but it gives me the same error.
gcc-4.8: error: language objective-c not recognized
gcc-4.8: error: language objective-c not recognized
cabal: Error: some packages failed to install:
fsnotify-0.0.11 depends on hfsevents-0.1.4 which failed to install.
hfsevents-0.1.4 failed during the building phase. The exception was:
ExitFailure 1
yesod-bin-1.2.3.4 depends on hfsevents-0.1.4 which failed to install.
How shall I proceed in order to install Yesod?
回答1:
I think this fixed it for me:
$ brew uninstall gcc48
$ brew install gcc48 --enable-all-languages
Presumably the default gcc48 doesn't include Objective-C.
回答2:
I ran into that same error—among many others—trying to install yesod on 10.8.5. I had some luck uninstalling the package from Haskell and installing Haskell via Homebrew. I did upgrade to 10.9 and everything still works (but I had to re-install Xcode command line tools)
I documented installing yesod on os x on my site if you need details.
来源：https://stackoverflow.com/questions/19758766/problems-installing-yesod-for-haskell