anchor.diff:          sha256 = ""; # TODO: uncomment and check hash when available.
         }) */
         ++ optional langAda ../gnat-cflags.patch
  -      ++ optional langAda (fetchpatch {
  -        name = "gnat-glibc-234.diff";
  -        url = "https://github.com/gcc-mirror/gcc/commit/331763de7d4850702a0f67298f36017c73cdb103.diff";
  -        sha256 = "eS4B7vJasnv2N+5v5yB8/iDpKPX8CJDAy2xabWWj+aU=";
  -      })
         ++ optional langD ../libphobos.patch
         ++ optional langFortran ../gfortran-driving.patch
         ++ optional (targetPlatform.libc == "musl" && targetPlatform.isPower) ../ppc-musl.patch
   
         # Obtain latest patch with ../update-mcfgthread-patches.sh
         ++ optional (!crossStageStatic && targetPlatform.isMinGW) ./Added-mcf-thread-model-support-from-mcfgthread.patch
  -
  -      ++ [ ../libsanitizer-no-cyclades-9.patch ];
  +      ;
   
       /* Cross-gcc settings (build == host != target) */
       crossMingw = targetPlatform != hostPlatform && targetPlatform.libc == "msvcrt";
  
positive.code: 
    src = fetchurl {
      url = "mirror://gcc/releases/gcc-${version}/gcc-${version}.tar.xz";
      sha256 = "1la2yy27ziasyf0jvzk58y1i5b5bq2h176qil550bxhifs39gqbi";
    };
  
    inherit patches;
  
negative.code: with builtins;
  
  let majorVersion = "9";
      version = "${majorVersion}.5.0";
  
      inherit (stdenv) buildPlatform hostPlatform targetPlatform;
  
      patches =
        [ ]
        ++ optional (targetPlatform != hostPlatform) ../libstdc++-target.patch
        ++ optional targetPlatform.isNetBSD ../libstdc++-netbsd-ctypes.patch
        ++ optional noSysDirs ../no-sys-dirs.patch
  