pdsh used to fail with an error because it couldn't locate libgcc_s.so.1.

Adding NIX_LDFLAGS="-lgcc_s" to the expression remedies that problem. Arguably,
though, this is a bad solution.

svn path=/nixpkgs/trunk/; revision=16239

pkgs/tools/networking/pdsh/default.nix

@@ -12,6 +12,12 @@ stdenv.mkDerivation rec {
     sha256 = "8c94acb17b4af8a9f553db180b4d5745c9c98844a5dc070e2ce80590e8e8a539";
   };
   buildInputs = [perl readline ssh pam];
+
+  /* pdsh uses pthread_cancel(), which requires libgcc_s.so.1 to be
+     loadable at run-time. Adding the flag below ensures that the
+     library can be found. Obviously, though, this is a hack. */
+  NIX_LDFLAGS="-lgcc_s";
+
   # Setting --with-machines=$out in configureFlags doesn't seem to work,
   # so I specify configurePhase instead.
   configurePhase = "./configure --prefix=$out --with-machines=$out/etc/machines"