Aargh! The Windows build has broken - again. I can't build GHC on my laptop any more. A clean 'sh validate' finishes as below. What on earth is `___sync_fetch_and_add_1'? Can anyone help? Thanks! Simon "inplace/bin/ghc-stage2.exe" -hisuf hi -osuf o -hcsuf hc -static -H32m -O -Werror -Wall -H64m -O0 -package-name vector-0.10.9.1 -hide-all-packages -i -ilibraries/vector/. -ilibraries/vector/dist-install/build -ilibraries/vector/dist-install/build/autogen -Ilibraries/vector/dist-install/build -Ilibraries/vector/dist-install/build/autogen -Ilibraries/vector/include -Ilibraries/vector/internal -optP-DVECTOR_BOUNDS_CHECKS -optP-include -optPlibraries/vector/dist-install/build/autogen/cabal_macros.h -package base-4.7.1.0 -package deepseq-1.3.0.2 -package ghc-prim-0.3.1.0 -package primitive-0.5.2.1 -O2 -XHaskell98 -XCPP -XDeriveDataTypeable -O2 -O -dcore-lint -fno-warn-deprecated-flags -no-user-package-db -rtsopts -Wwarn -odir libraries/vector/dist-install/build -hidir libraries/vector/dist-install/build -stubdir libraries/vector/dist-install/build -c libraries/vector/./Data/Vector/Fusion/Stream/Monadic.hs -o libraries/vector/dist-install/build/Data/Vector/Fusion/Stream/Monadic.o Loading package ghc-prim ... linking ... ghc-stage2.exe: unable to load package `ghc-prim' ghc-stage2.exe: C:\code\HEAD\libraries\ghc-prim\dist-install\build\HSghc-prim-0.3.1.0.o: unknown symbol `___sync_fetch_and_add_1' libraries/vector/ghc.mk:5: recipe for target 'libraries/vector/dist-install/build/Data/Vector/Fusion/Stream/Monadic.o' failed make[1]: *** [libraries/vector/dist-install/build/Data/Vector/Fusion/Stream/Monadic.o] Error 1 I