gsl: remove disable-fma.patch

`NIX_CFLAGS_COMPILE = [ "-mno-fma" ];` disables FMA in a more reliable way.

`platform.gcc.arch = "skylake"` resulting in gcc command line flag -march=skylake was able to enable FMA even with disable-fma.patch applied

pkgs/development/libraries/gsl/default.nix

@@ -10,11 +10,6 @@ stdenv.mkDerivation rec {
 
   NIX_CFLAGS_COMPILE = [ "-mno-fma" ]; # do not let -march=skylake to enable FMA (https://lists.gnu.org/archive/html/bug-gsl/2011-11/msg00019.html)
 
-  patches = [
-    # ToDo: there might be more impurities than FMA support check
-    ./disable-fma.patch # https://lists.gnu.org/archive/html/bug-gsl/2011-11/msg00019.html
-  ];
-
   # https://lists.gnu.org/archive/html/bug-gsl/2015-11/msg00012.html
   doCheck = stdenv.hostPlatform.system != "i686-linux" && stdenv.hostPlatform.system != "aarch64-linux";
 

pkgs/development/libraries/gsl/disable-fma.patch

@@ -1,32 +0,0 @@
---- a/configure.ac        2011-09-22 16:13:22 +0000
-+++ b/configure.ac        2011-11-26 23:55:24 +0000
-@@ -381,6 +381,28 @@
- AC_SUBST(HAVE_DARWIN_IEEE_INTERFACE)
- AC_SUBST(HAVE_DARWIN86_IEEE_INTERFACE)
- 
-+dnl check for compiler flags to disable use of FMA
-+save_cflags="$CFLAGS"
-+AC_CACHE_CHECK([for compiler flags to disable use of FMA], ac_cv_c_fma_flags,
-+[
-+if test X"$GCC" = Xyes; then
-+    fma_flags='-ffp-contract=off'
-+else
-+    fma_flags=
-+fi
-+if test X"$fma_flags" != X; then
-+  CFLAGS="$fma_flags $CFLAGS"
-+  AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]], [[int foo;]])],[ac_cv_c_fma_flags="$fma_flags"],[ac_cv_c_fma_flags="none"])
-+else
-+  ac_cv_c_fma_flags="none"
-+fi])
-+
-+if test "$ac_cv_c_fma_flags" != "none" ; then
-+   CFLAGS="$ac_cv_c_fma_flags $save_cflags"
-+else
-+   CFLAGS="$save_cflags"
-+fi
-+
- dnl Check for IEEE control flags
- 
- save_cflags="$CFLAGS"
-

pkgs/development/libraries/gsl/gsl-1_16.nix

@@ -11,8 +11,6 @@ stdenv.mkDerivation rec {
   NIX_CFLAGS_COMPILE = [ "-mno-fma" ]; # do not let -march=skylake to enable FMA (https://lists.gnu.org/archive/html/bug-gsl/2011-11/msg00019.html)
 
   patches = [
-    # ToDo: there might be more impurities than FMA support check
-    ./disable-fma.patch # https://lists.gnu.org/archive/html/bug-gsl/2011-11/msg00019.html
     (fetchpatch {
       name = "bug-39055.patch";
       url = "https://git.savannah.gnu.org/cgit/gsl.git/patch/?id=9cc12d";