diff --git a/pkgs/misc/screensavers/xscreensaver/default.nix b/pkgs/misc/screensavers/xscreensaver/default.nix
index cb937a94000..1d039e0a440 100644
--- a/pkgs/misc/screensavers/xscreensaver/default.nix
+++ b/pkgs/misc/screensavers/xscreensaver/default.nix
@@ -18,14 +18,15 @@ stdenv.mkDerivation rec {
       libXxf86misc intltool
     ];
 
-  patchPhase =
+  preConfigure =
     ''
       # Fix build error in version 5.18. Remove this patch when updating
       # to a later version.
       #sed -i -e '/AF_LINK/d' hacks/glx/sonar-icmp.c
-      # Fix path to GTK.
+
+      # Fix installation paths for GTK resources.
       sed -e 's%@GTK_DATADIR@%@datadir@% ; s%@PO_DATADIR@%@datadir@%' \
-	  -i driver/Makefile.in po/Makefile.in.in
+          -i driver/Makefile.in po/Makefile.in.in
     '';
 
   configureFlags =
diff --git a/pkgs/top-level/emacs-packages.nix b/pkgs/top-level/emacs-packages.nix
index a5a087e16ad..4b23992d12a 100644
--- a/pkgs/top-level/emacs-packages.nix
+++ b/pkgs/top-level/emacs-packages.nix
@@ -454,6 +454,7 @@ let self = _self // overrides;
     pname = "ghc";
     version = external.ghc-mod.version;
     src = external.ghc-mod.src;
+    propagatedUserEnvPkgs = [ external.ghc-mod ];
     fileSpecs = [ "elisp/*.el" ];
     meta = { license = bsd3; };
   };
diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index ed13c3e187b..b1e7e2b3352 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -6902,7 +6902,7 @@ let
 
     src = pkgs.notmuch.src;
 
-    sourceRoot = "${pkgs.notmuch.name}/bindings/python";
+    sourceRoot = "${pkgs.notmuch.src.name}/bindings/python";
 
     buildInputs = with self; [ python pkgs.notmuch ];