diff --git a/pkgs/development/libraries/gmp/5.1.x.nix b/pkgs/development/libraries/gmp/5.1.x.nix
index 53d7f4585659..cba8d394c2ba 100644
--- a/pkgs/development/libraries/gmp/5.1.x.nix
+++ b/pkgs/development/libraries/gmp/5.1.x.nix
@@ -1,5 +1,7 @@
 { stdenv, fetchurl, m4, cxx ? true }:
 
+with { inherit (stdenv.lib) optional; };
+
 stdenv.mkDerivation rec {
   name = "gmp-5.1.3";
 
@@ -14,10 +16,12 @@ stdenv.mkDerivation rec {
     # Build a "fat binary", with routines for several sub-architectures
     # (x86), except on Solaris where some tests crash with "Memory fault".
     # See <http://hydra.nixos.org/build/2760931>, for instance.
-    (stdenv.lib.optional (!stdenv.isSunOS) "--enable-fat")
-    ++ (if cxx then [ "--enable-cxx" "CPPFLAGS=-fexceptions" ]
+    optional (!stdenv.isSunOS) "--enable-fat"
+    ++ (if cxx then [ "--enable-cxx"  ]
                else [ "--disable-cxx" ])
-    ++ (if stdenv.is64bit then [ "--with-pic" ] else []);
+    ++ optional (cxx && stdenv.isDarwin) "CPPFLAGS=-fexceptions"
+    ++ optional stdenv.is64bit "--with-pic"
+    ;
 
   doCheck = true;
 
diff --git a/pkgs/development/libraries/ppl/default.nix b/pkgs/development/libraries/ppl/default.nix
index 2c22317a6ca7..e3b1444b8cb3 100644
--- a/pkgs/development/libraries/ppl/default.nix
+++ b/pkgs/development/libraries/ppl/default.nix
@@ -13,8 +13,9 @@ stdenv.mkDerivation rec {
   nativeBuildInputs = [ perl gnum4 ];
   propagatedBuildInputs = [ gmpxx ];
 
-  configureFlags = [ "--disable-watchdog" "CPPFLAGS=-fexceptions" ] ++
+  configureFlags = [ "--disable-watchdog" ] ++
     stdenv.lib.optionals stdenv.isDarwin [
+      "CPPFLAGS=-fexceptions"
       "--disable-ppl_lcdd" "--disable-ppl_lpsol" "--disable-ppl_pips"
     ];