This breakage didn't use to happen. Might someone fix it? Thanks. For now I'm going through changing a dozen "Trustworthy" to "Safe". Is that right? Simon librariesWin32SystemWin32Console.hsc:2:14: Warning: 'System.Win32.Console' is marked as Trustworthy but has been inferred as safe! <no location info>: Failing due to -Werror. libraries/Win32/ghc.mk:4: recipe for target 'libraries/Win32/dist-install/build/System/Win32/Console.o' failed