#if __GLASGOW_HASKELL__ < 604 || (__GLASGOW_HASKELL__==604 && __GHC_PATCHLEVEL__==0)
#include "WCsubst.c"
#endif

#if __GLASGOW_HASKELL__ < 605
#if __GLASGOW_HASKELL__ != 604 || __GHC_PATCHLEVEL__ == 0
#include "WCsubst.c"
#endif
#endif

Fix building with compilers which don't have an integer for a patch level
Fix building with compilers which don't have an integer for a patch level