fftw: minor update and major refactoring

- Unify the "single" and "float" variants, which are the same thing.
- Enable threads and openmp wrapper by default (they are very small).
- Don't use sse on i686, as I'm quite sure we have no warrant for that.
  Cf. http://en.wikipedia.org/wiki/Pentium_Pro
- Disable static libs (big, no indication we need them).
- I tested most builds using fftw (they build OK).

pkgs/development/libraries/fftw/default.nix

@@ -1,30 +1,32 @@
-{fetchurl, stdenv, builderDefs, stringsWithDeps, singlePrecision ? false, pthreads ? false, float ? false}:
+{ fetchurl, stdenv, builderDefs, precision ? "double" }:
+
+assert stdenv.lib.elem precision [ "single" "double" "long-double" "quad-precision" ];
+
+with { inherit (stdenv.lib) optional; };
+
 let
-  version = "3.3.2";
-  localDefs = builderDefs.passthru.function { 
-  src = 
-    fetchurl {
-      url = "ftp://ftp.fftw.org/pub/fftw/fftw-${version}.tar.gz";
-      sha256 = "b1236a780ca6e66fc5f8eda6ef0665d680e8253d9f01d7bf211b714a50032d01";
-    };
-  buildInputs = [];
-  configureFlags = ["--enable-shared"]
-                        # some distros seem to be shipping both versions within the same package?
-                        # why does --enable-float still result in ..3f.so instead of ..3.so?
-                   ++ (if singlePrecision then [ "--enable-single" ] else [ ])
-                   ++ (if float then [ "--enable-float" ] else [ ])
-		   ++ (stdenv.lib.optional (!pthreads) "--enable-openmp")
-		   ++ (stdenv.lib.optional pthreads "--enable-threads")
-                        # I think all i686 has sse
-                   ++ (if (stdenv.isi686 || stdenv.isx86_64) && singlePrecision then [ "--enable-sse" ] else [ ])
-                        # I think all x86_64 has sse2
-                   ++ (if stdenv.isx86_64 && ! singlePrecision then [ "--enable-sse2" ] else [ ]);
-                
+  version = "3.3.3";
+  localDefs = builderDefs.passthru.function {
+    src =
+      fetchurl {
+        url = "ftp://ftp.fftw.org/pub/fftw/fftw-${version}.tar.gz";
+        sha256 = "1wwp9b2va7vkq3ay7a9jk22nr4x5q6m37rzqy2j8y3d11c5grkc5";
+      };
+    buildInputs = [];
+    configureFlags = [
+        "--enable-shared" "--disable-static"
+        "--enable-threads" "--enable-openmp" # very small wrappers
+      ]
+      ++ optional (precision != "double") "--enable-${precision}"
+      # all x86_64 have sse2
+      ++ optional stdenv.isx86_64 "--enable-sse2";
   };
+
 in with localDefs;
-stdenv.mkDerivation {
-  name = "fftw-3.3.2" + ( if singlePrecision then "-single" else "-double" );
-  builder = writeScript "fftw-3.3.2-builder"
+
+stdenv.mkDerivation rec {
+  name = "fftw-${precision}-${version}";
+  builder = writeScript "${name}-builder"
     (textClosure localDefs [doConfigure doMakeInstall doForceShare]);
   meta = {
     description = "Fastest Fourier Transform in the West library";
@@ -34,3 +36,4 @@ stdenv.mkDerivation {
     inherit src;
   };
 }
+