Fixed a segfault that could occur when calling mkWeakForeignEnv#.

Fixed a crash that could occur when calling unblock inside unsafePerformIO.

Stop primops such as readMutVar# being inlined, which can cause loss of referential transparency.

Fixed a bug that meant ctrl-C was ignored by processes we run with runProcess.

Fixed a bug where gcc processes run by GHC get killed on Mac OS X 10.4.11.

Fixed a bug where processes on Windows could hold file handles open after they had finished, leading to permission denied errors.

GHCi only uses Haskeline if the input is a terminal.

Fixed building with newer versions of MSYS binutils.