I can't see how VIM could do anything to your GHDL installation, perhaps it was syntastic that replaced something with a new version that GHDL is incompatible with.
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You would probably be better off downloading Altera's free web tool suite and the free version of Modelsim they have. It would compile the above code without problems (I checked it both on Modelsim and Vivado, though I am using the PC version).