hello all, i'm getting the following error quite consistently on OSX, for getting the docs working / built and its quite impossible to install if the docs aren't fully built i've bolded below an except how do i fix thisssss please help meeeee :) many thanks. *Extension error:* *The 'ghc-flag' directive is already registered to domain std* *docs/users_guide/ghc.mk:16 http://ghc.mk:16: recipe for target 'docs/users_guide/users_guide.pdf' failed* *make[1]: *** [docs/users_guide/users_guide.pdf] Error 2* *make[1]: *** Waiting for unfinished jobs....* *Extension error:* *The 'ghc-flag' directive is already registered to domain std* *Extension error:* *The 'ghc-flag' directive is already registered to domain std* *docs/users_guide/ghc.mk:28 http://ghc.mk:28: recipe for target 'docs/users_guide/build-man/ghc.1' failed* the full end of the build is as follows any /usr/local/bin/ginstall -c -m 755 utils/genapply/dist/build/tmp/genapply inplace/lib/bin/genapply cp libffi/build/inst/lib/libffi.a rts/dist/build/libCffi.a "inplace/bin/ghc-stage1" -hisuf hi -osuf o -hcsuf hc -static -H32m -O -Wall -this-unit-id ghc-prim-0.5.2.0 -hide-all-packages -i -ilibraries/ghc-prim/. -ilibraries/ghc-prim/dist-install/build -Ilibraries/ghc-prim/dist-install/build -ilibraries/ghc-prim/dist-install/build/./autogen -Ilibraries/ghc-prim/dist-install/build/./autogen -Ilibraries/ghc-prim/. -optP-include -optPlibraries/ghc-prim/dist-install/build/./autogen/cabal_macros.h -package-id rts -this-unit-id ghc-prim -XHaskell2010 -O2 -no-user-package-db -rtsopts -Wno-trustworthy-safe -Wno-deprecated-flags -Wnoncanonical-monad-instances -odir libraries/ghc-prim/dist-install/build -hidir libraries/ghc-prim/dist-install/build -stubdir libraries/ghc-prim/dist-install/build -dynamic-too -c libraries/ghc-prim/./GHC/Tuple.hs -o libraries/ghc-prim/dist-install/build/GHC/Tuple.o -dyno libraries/ghc-prim/dist-install/build/GHC/Tuple.dyn_o Running Sphinx v1.8.1 Running Sphinx v1.8.1 Running Sphinx v1.8.1 loading pickled environment... done building [mo]: targets for 0 po files that are out of date building [html]: targets for 4 source files that are out of date updating environment: 0 added, 0 changed, 0 removed looking for now-outdated files... none found pickling environment... done preparing documents... done writing output... [ 25%] index Extension error: The 'ghc-flag' directive is already registered to domain std docs/users_guide/ghc.mk:16: recipe for target 'docs/users_guide/users_guide.pdf' failed make[1]: *** [docs/users_guide/users_guide.pdf] Error 2 make[1]: *** Waiting for unfinished jobs.... Extension error: The 'ghc-flag' directive is already registered to domain std Extension error: The 'ghc-flag' directive is already registered to domain std docs/users_guide/ghc.mk:28: recipe for target 'docs/users_guide/build-man/ghc.1' failed make[1]: *** [docs/users_guide/build-man/ghc.1] Error 2 docs/users_guide/ghc.mk:16: recipe for target 'docs/users_guide/build-html/users_guide/index.html' failed make[1]: *** [docs/users_guide/build-html/users_guide/index.html] Error 2 writing output... [100%] markup /Users/carter/dev-checkouts/ghc-tree/ghc-8.4.4-checkout-clang-build/utils/haddock/doc/invoking.rst:457: WARNING: unknown option: -cpp generating indices... genindex writing additional pages... search copying static files... done copying extra files... done dumping search index in English (code: en) ... done dumping object inventory... done build succeeded, 1 warning. The HTML pages are in .build-html. cp -R utils/haddock/doc/.build-html utils/haddock/doc/haddock Makefile:122: recipe for target 'all' failed make: *** [all] Error 2