diff -up ghc-7.0.2/aclocal.m4.pthread ghc-7.0.2/aclocal.m4

--- ghc-7.0.2/aclocal.m4.pthread	2011-02-28 13:10:03.000000000 -0500

+++ ghc-7.0.2/aclocal.m4	2011-04-20 07:12:36.489772545 -0400

@@ -1385,7 +1385,7 @@ AC_MSG_NOTICE(Building in-tree ghc-pwd)

     dnl except we don't want to have to know what make is called. Sigh.

     rm -rf utils/ghc-pwd/dist-boot

     mkdir  utils/ghc-pwd/dist-boot

-    if ! "$WithGhc" -v0 -no-user-package-conf -hidir utils/ghc-pwd/dist-boot -odir utils/ghc-pwd/dist-boot -stubdir utils/ghc-pwd/dist-boot --make utils/ghc-pwd/Main.hs -o utils/ghc-pwd/dist-boot/ghc-pwd

+    if ! "$WithGhc" -optl-pthread -v0 -no-user-package-conf -hidir utils/ghc-pwd/dist-boot -odir utils/ghc-pwd/dist-boot -stubdir utils/ghc-pwd/dist-boot --make utils/ghc-pwd/Main.hs -o utils/ghc-pwd/dist-boot/ghc-pwd

     then

         AC_MSG_ERROR([Building ghc-pwd failed])

     fi

diff -up ghc-7.0.2/ghc/ghc.wrapper.pthread ghc-7.0.2/ghc/ghc.wrapper

--- ghc-7.0.2/ghc/ghc.wrapper.pthread	2011-04-20 09:58:50.307894773 -0400

+++ ghc-7.0.2/ghc/ghc.wrapper	2011-04-20 09:59:14.477894370 -0400

@@ -1 +1 @@

-exec "$executablename" -B"$topdir" -pgmc "$pgmgcc" -pgma "$pgmgcc" -pgml "$pgmgcc" -pgmP "$pgmgcc -E -undef -traditional" ${1+"$@"}

+exec "$executablename" -B"$topdir" -pgmc "$pgmgcc" -pgma "$pgmgcc" -pgml "$pgmgcc" -pgmP "$pgmgcc -E -undef -traditional" -optl-pthread ${1+"$@"}