Merge remote-tracking branch 'upstream/master' into gcc8

pkgs/development/compilers/gcc/8/default.nix

@@ -54,22 +54,6 @@ let version = "8.1.0";
       }) */
       ++ optional langFortran ../gfortran-driving.patch;
 
-    /* Platform flags */
-    platformFlags = let
-        gccArch = targetPlatform.platform.gcc.arch or null;
-        gccCpu = targetPlatform.platform.gcc.cpu or null;
-        gccAbi = targetPlatform.platform.gcc.abi or null;
-        gccFpu = targetPlatform.platform.gcc.fpu or null;
-        gccFloat = targetPlatform.platform.gcc.float or null;
-        gccMode = targetPlatform.platform.gcc.mode or null;
-      in
-        optional (gccArch != null) "--with-arch=${gccArch}" ++
-        optional (gccCpu != null) "--with-cpu=${gccCpu}" ++
-        optional (gccAbi != null) "--with-abi=${gccAbi}" ++
-        optional (gccFpu != null) "--with-fpu=${gccFpu}" ++
-        optional (gccFloat != null) "--with-float=${gccFloat}" ++
-        optional (gccMode != null) "--with-mode=${gccMode}";
-
     /* Cross-gcc settings (build == host != target) */
     crossMingw = targetPlatform != hostPlatform && targetPlatform.libc == "msvcrt";
     crossDarwin = targetPlatform != hostPlatform && targetPlatform.libc == "libSystem";
@@ -178,11 +162,7 @@ stdenv.mkDerivation ({
       patchShebangs $configureScript
     done
   '' + (
-    if (hostPlatform.isHurd
-        || (libcCross != null                  # e.g., building `gcc.crossDrv'
-            && libcCross ? crossConfig
-            && libcCross.crossConfig == "i586-pc-gnu")
-        || (crossGNU && libcCross != null))
+    if targetPlatform.isHurd
     then
       # On GNU/Hurd glibc refers to Hurd & Mach headers and libpthread is not
       # in glibc, so add the right `-I' flags to the default spec string.
@@ -331,7 +311,7 @@ stdenv.mkDerivation ({
     # Optional features
     optional (isl != null) "--with-isl=${isl}" ++
 
-    platformFlags ++
+    (import ../common/platform-flags.nix { inherit (stdenv) lib targetPlatform; }) ++
     optional (targetPlatform != hostPlatform) crossConfigureFlags ++
     optional (!bootstrap) "--disable-bootstrap" ++