Darwin platform versions

lib/systems/default.nix

@@ -112,6 +112,19 @@ rec {
         aarch64 = "arm64";
       }.${final.parsed.cpu.name} or final.parsed.cpu.name;
 
+      darwinPlatform =
+        if final.isMacOS then "macos"
+        else if final.isiOS then "ios"
+        else null;
+      # The canonical name for this attribute is darwinSdkVersion, but some
+      # platforms define the old name "sdkVer".
+      darwinSdkVersion = final.sdkVer or "10.12";
+      darwinMinVersion = final.darwinSdkVersion;
+      darwinMinVersionVariable =
+        if final.isMacOS then "MACOSX_DEPLOYMENT_TARGET"
+        else if final.isiOS then "IPHONEOS_DEPLOYMENT_TARGET"
+        else null;
+
       emulator = pkgs: let
         qemu-user = pkgs.qemu.override {
           smartcardSupport = false;

lib/systems/examples.nix

@@ -219,6 +219,7 @@ rec {
     sdkVer = "14.3";
     xcodeVer = "12.3";
     xcodePlatform = "iPhoneSimulator";
+    darwinPlatform = "ios-simulator";
     useiOSPrebuilt = true;
   };
 
@@ -228,6 +229,7 @@ rec {
     sdkVer = "14.3";
     xcodeVer = "12.3";
     xcodePlatform = "iPhoneSimulator";
+    darwinPlatform = "ios-simulator";
     useiOSPrebuilt = true;
   };
 

pkgs/build-support/bintools-wrapper/add-darwin-ldflags-before.sh

@@ -0,0 +1,81 @@
+# Unconditionally adding in platform version flags will result in warnings that
+# will be treated as errors by some packages. Add any missing flags here.
+
+# There are two things to be configured: the "platform version" (oldest
+# supported version of macos, ios, etc), and the "sdk version".
+#
+# The modern way of configuring these is to use:
+#    -platform_version $platform $platform_version $sdk_version"
+#
+# The old way is still supported, and uses flags like:
+#    -${platform}_version_min $platform_version
+#    -sdk_version $sdk_version
+#
+# If both styles are specified ld will combine them. If multiple versions are
+# specified for the same platform, ld will emit an error.
+#
+# The following adds flags for whichever properties have not already been
+# provided.
+
+havePlatformVersionFlag=
+haveDarwinSDKVersion=
+haveDarwinPlatformVersion=
+
+# Roles will set by add-flags.sh, but add-flags.sh can be skipped when the
+# cc-wrapper has added the linker flags. Both the cc-wrapper and the binutils
+# wrapper mangle the same variable (MACOSX_DEPLOYMENT_TARGET), so if roles are
+# empty due to being run through the cc-wrapper then the mangle here is a no-op
+# and we still do the right thing.
+#
+# To be robust, make sure we always have the correct set of roles.
+accumulateRoles
+
+mangleVarSingle @darwinMinVersionVariable@ ${role_suffixes[@]+"${role_suffixes[@]}"}
+
+n=0
+nParams=${#params[@]}
+while (( n < nParams )); do
+    p=${params[n]}
+    case "$p" in
+        # the current platform
+        -@darwinPlatform@_version_min)
+            haveDarwinPlatformVersion=1
+            ;;
+
+        # legacy aliases
+        -macosx_version_min|-iphoneos_version_min|-iosmac_version_min|-uikitformac_version_min)
+            haveDarwinPlatformVersion=1
+            ;;
+
+        -sdk_version)
+            haveDarwinSDKVersion=1
+            ;;
+
+        -platform_version)
+            havePlatformVersionFlag=1
+
+            # If clang can't determine the sdk version it will pass 0.0.0. This
+            # has runtime effects so we override this to use the known sdk
+            # version.
+            if [ "${params[n+3]-}" = 0.0.0 ]; then
+                params[n+3]=@darwinSdkVersion@
+            fi
+            ;;
+    esac
+    n=$((n + 1))
+done
+
+# If the caller has set -platform_version, trust they're doing the right thing.
+# This will be the typical case for clang in nixpkgs.
+if [ ! "$havePlatformVersionFlag" ]; then
+    if [ ! "$haveDarwinSDKVersion" ] && [ ! "$haveDarwinPlatformVersion" ]; then
+        # Nothing provided. Use the modern "-platform_version" to set both.
+        extraBefore+=(-platform_version @darwinPlatform@ "${@darwinMinVersionVariable@_@suffixSalt@:-@darwinMinVersion@}" @darwinSdkVersion@)
+    elif [ ! "$haveDarwinSDKVersion" ]; then
+        # Add missing sdk version
+        extraBefore+=(-sdk_version @darwinSdkVersion@)
+    elif [ ! "$haveDarwinPlatformVersion" ]; then
+        # Add missing platform version
+        extraBefore+=(-@darwinPlatform@_version_min "${@darwinMinVersionVariable@_@suffixSalt@:-@darwinMinVersion@}")
+    fi
+fi

pkgs/build-support/bintools-wrapper/default.nix

@@ -252,11 +252,6 @@ stdenv.mkDerivation {
       fi
     '')
 
-    # Ensure consistent LC_VERSION_MIN_MACOSX and remove LC_UUID.
-    + optionalString stdenv.targetPlatform.isMacOS ''
-      echo "-sdk_version 10.12 -no_uuid" >> $out/nix-support/libc-ldflags-before
-    ''
-
     ##
     ## User env support
     ##
@@ -310,6 +305,13 @@ stdenv.mkDerivation {
       echo "-arch ${targetPlatform.darwinArch}" >> $out/nix-support/libc-ldflags
     ''
 
+    ###
+    ### Remove LC_UUID
+    ###
+    + optionalString (stdenv.targetPlatform.isDarwin && !(stdenv.cc.bintools.bintools.isGNU or false)) ''
+      echo "-no_uuid" >> $out/nix-support/libc-ldflags-before
+    ''
+
     + ''
       for flags in "$out/nix-support"/*flags*; do
         substituteInPlace "$flags" --replace $'\n' ' '
@@ -320,6 +322,23 @@ stdenv.mkDerivation {
       substituteAll ${../wrapper-common/utils.bash} $out/nix-support/utils.bash
     ''
 
+    ###
+    ### Ensure consistent LC_VERSION_MIN_MACOSX
+    ###
+    + optionalString stdenv.targetPlatform.isDarwin (
+      let
+        inherit (stdenv.targetPlatform)
+          darwinPlatform darwinSdkVersion
+          darwinMinVersion darwinMinVersionVariable;
+      in ''
+        export darwinPlatform=${darwinPlatform}
+        export darwinMinVersion=${darwinMinVersion}
+        export darwinSdkVersion=${darwinSdkVersion}
+        export darwinMinVersionVariable=${darwinMinVersionVariable}
+        substituteAll ${./add-darwin-ldflags-before.sh} $out/nix-support/add-local-ldflags-before.sh
+      ''
+    )
+
     ##
     ## Extra custom steps
     ##

pkgs/build-support/bintools-wrapper/ld-wrapper.sh

@@ -78,6 +78,14 @@ fi
 
 extraAfter+=($NIX_LDFLAGS_AFTER_@suffixSalt@)
 
+# These flags *must not* be pulled up to -Wl, flags, so they can't go in
+# add-flags.sh. They must always be set, so must not be disabled by
+# NIX_LDFLAGS_SET.
+if [ -e @out@/nix-support/add-local-ldflags-before.sh ]; then
+    source @out@/nix-support/add-local-ldflags-before.sh
+fi
+
+
 # Specify the target emulation if nothing is passed in ("-m" overrides this
 # environment variable). Ensures we never blindly fallback on targeting the host
 # platform.

pkgs/build-support/cc-wrapper/add-flags.sh

@@ -65,5 +65,13 @@ if [ -e @out@/nix-support/cc-cflags-before ]; then
     NIX_CFLAGS_COMPILE_BEFORE_@suffixSalt@="$(< @out@/nix-support/cc-cflags-before) $NIX_CFLAGS_COMPILE_BEFORE_@suffixSalt@"
 fi
 
+# Only add darwin min version flag if a default darwin min version is set,
+# which is a signal that we're targetting darwin.
+if [ "@darwinMinVersion@" ]; then
+    mangleVarSingle @darwinMinVersionVariable@ ${role_suffixes[@]+"${role_suffixes[@]}"}
+
+    NIX_CFLAGS_COMPILE_BEFORE_@suffixSalt@="-m@darwinPlatformForCC@-version-min=${@darwinMinVersionVariable@_@suffixSalt@:-@darwinMinVersion@} $NIX_CFLAGS_COMPILE_BEFORE_@suffixSalt@"
+fi
+
 # That way forked processes will not extend these environment variables again.
 export NIX_CC_WRAPPER_FLAGS_SET_@suffixSalt@=1

pkgs/build-support/cc-wrapper/default.nix

@@ -100,6 +100,18 @@ let
     else
       false;
 
+
+  darwinPlatformForCC = optionalString stdenv.targetPlatform.isDarwin (
+    if (targetPlatform.darwinPlatform == "macos" && isGNU) then "macosx"
+    else targetPlatform.darwinPlatform
+  );
+
+  darwinMinVersion = optionalString stdenv.targetPlatform.isDarwin (
+    stdenv.targetPlatform.darwinMinVersion
+  );
+
+  darwinMinVersionVariable = optionalString stdenv.targetPlatform.isDarwin
+    stdenv.targetPlatform.darwinMinVersionVariable;
 in
 
 # Ensure bintools matches
@@ -122,6 +134,7 @@ stdenv.mkDerivation {
   gnugrep_bin = if nativeTools then "" else gnugrep;
 
   inherit targetPrefix suffixSalt;
+  inherit darwinPlatformForCC darwinMinVersion darwinMinVersionVariable;
 
   outputs = [ "out" ] ++ optionals propagateDoc [ "man" "info" ];
 
@@ -473,6 +486,10 @@ stdenv.mkDerivation {
       done
     ''
 
+    + optionalString stdenv.targetPlatform.isDarwin ''
+        echo "-arch ${targetPlatform.darwinArch}" >> $out/nix-support/cc-cflags
+    ''
+
     # There are a few tools (to name one libstdcxx5) which do not work
     # well with multi line flags, so make the flags single line again
     + ''
@@ -485,10 +502,6 @@ stdenv.mkDerivation {
       substituteAll ${../wrapper-common/utils.bash} $out/nix-support/utils.bash
     ''
 
-    + optionalString stdenv.targetPlatform.isDarwin ''
-      echo "-arch ${targetPlatform.darwinArch}" >> $out/nix-support/cc-cflags
-    ''
-
     ##
     ## Extra custom steps
     ##

pkgs/build-support/wrapper-common/utils.bash

@@ -49,6 +49,35 @@ mangleVarBool() {
     done
 }
 
+# Combine a singular value from all roles. If multiple roles are being served,
+# and the value differs in these roles then the request is impossible to
+# satisfy and we abort immediately.
+mangleVarSingle() {
+    local var="$1"
+    shift
+    local -a role_suffixes=("$@")
+
+    local outputVar="${var}_@suffixSalt@"
+    for suffix in "${role_suffixes[@]}"; do
+        local inputVar="${var}${suffix}"
+        if [ -v "$inputVar" ]; then
+            if [ -v "$outputVar" ]; then
+                if [ "${!outputVar}" != "${!inputVar}" ]; then
+                    {
+                        echo "Multiple conflicting values defined for $outputVar"
+                        echo "Existing value is ${!outputVar}"
+                        echo "Attempting to set to ${!inputVar} via $inputVar"
+                    } >&2
+
+                    exit 1
+                fi
+            else
+                declare -gx ${outputVar}="${!inputVar}"
+            fi
+        fi
+    done
+}
+
 skip () {
     if (( "${NIX_DEBUG:-0}" >= 1 )); then
         echo "skipping impure path $1" >&2

pkgs/development/tools/misc/binutils/default.nix

@@ -143,6 +143,7 @@ stdenv.mkDerivation {
 
   passthru = {
     inherit targetPrefix;
+    isGNU = true;
   };
 
   meta = with lib; {

pkgs/development/tools/misc/luarocks/darwin-3.1.3.patch

@@ -7,7 +7,7 @@ index c5af5a2..1949fdc 100644
        defaults.arch = "macosx-"..target_cpu
        defaults.variables.LIBFLAG = "-bundle -undefined dynamic_lookup -all_load"
 -      local version = util.popen_read("sw_vers -productVersion")
-+      local version = os.getenv("MACOSX_DEPLOYMENT_TARGET") or "10.12"
++      local version = os.getenv("MACOSX_DEPLOYMENT_TARGET") or "@darwinMinVersion@"
        version = tonumber(version and version:match("^[^.]+%.([^.]+)")) or 3
        if version >= 10 then
           version = 8

pkgs/development/tools/misc/luarocks/default.nix

@@ -19,6 +19,11 @@ stdenv.mkDerivation rec {
   };
 
   patches = [ ./darwin-3.1.3.patch ];
+
+  postPatch = lib.optionalString stdenv.targetPlatform.isDarwin ''
+    substituteInPlace src/luarocks/core/cfg.lua --subst-var-by 'darwinMinVersion' '${stdenv.targetPlatform.darwinMinVersion}'
+  '';
+
   preConfigure = ''
     lua -e "" || {
         luajit -e "" && {

pkgs/development/tools/xcbuild/wrapper.nix

@@ -3,7 +3,7 @@
 , runtimeShell, callPackage
 , xcodePlatform ? stdenv.targetPlatform.xcodePlatform or "MacOSX"
 , xcodeVer ? stdenv.targetPlatform.xcodeVer or "9.4.1"
-, sdkVer ? stdenv.targetPlatform.sdkVer or "10.12" }:
+, sdkVer ? stdenv.targetPlatform.darwinSdkVersion or "10.12" }:
 
 let
 

pkgs/os-specific/darwin/xcode/sdk-pkgs.nix

@@ -29,11 +29,6 @@ rec {
   binutils = wrapBintoolsWith {
     libc = targetIosSdkPkgs.libraries;
     bintools = binutils-unwrapped;
-    extraBuildCommands = lib.optionalString (sdk.platform == "iPhoneSimulator") ''
-      echo "-platform_version ios-sim ${minSdkVersion} ${sdk.version}" >> $out/nix-support/libc-ldflags
-    '' + lib.optionalString (sdk.platform == "iPhoneOS") ''
-      echo "-platform_version ios ${minSdkVersion} ${sdk.version}" >> $out/nix-support/libc-ldflags
-    '';
   };
 
   clang = (wrapCCWith {
@@ -46,10 +41,6 @@ rec {
       mv cc-cflags.tmp $out/nix-support/cc-cflags
       echo "-target ${targetPlatform.config}" >> $out/nix-support/cc-cflags
       echo "-isystem ${sdk}/usr/include${lib.optionalString (lib.versionAtLeast "10" sdk.version) " -isystem ${sdk}/usr/include/c++/4.2.1/ -stdlib=libstdc++"}" >> $out/nix-support/cc-cflags
-    '' + lib.optionalString (sdk.platform == "iPhoneSimulator") ''
-      echo "-mios-simulator-version-min=${minSdkVersion}" >> $out/nix-support/cc-cflags
-    '' + lib.optionalString (sdk.platform == "iPhoneOS") ''
-      echo "-miphoneos-version-min=${minSdkVersion}" >> $out/nix-support/cc-cflags
     '';
   }) // {
     inherit sdk;

pkgs/stdenv/darwin/default.nix

@@ -1,7 +1,5 @@
 { lib
 , localSystem, crossSystem, config, overlays, crossOverlays ? []
-# Minimum required macOS version, used both for compatibility as well as reproducability.
-, macosVersionMin ? "10.12"
 # Allow passing in bootstrap files directly so we can test the stdenv bootstrap process when changing the bootstrap tools
 , bootstrapFiles ? let
   fetch = { file, sha256, executable ? true }: import <nix/fetchurl.nix> {
@@ -36,8 +34,6 @@ in rec {
     export NIX_IGNORE_LD_THROUGH_GCC=1
     unset SDKROOT
 
-    export MACOSX_DEPLOYMENT_TARGET=${macosVersionMin}
-
     # Workaround for https://openradar.appspot.com/22671534 on 10.11.
     export gl_cv_func_getcwd_abort_bug=no
 
@@ -147,9 +143,6 @@ in rec {
         __stdenvImpureHostDeps = commonImpureHostDeps;
         __extraImpureHostDeps = commonImpureHostDeps;
 
-        extraAttrs = {
-          inherit macosVersionMin;
-        };
         overrides  = self: super: (overrides self super) // {
           inherit ccNoLibcxx;
           fetchurl = thisStdenv.fetchurlBoot;
@@ -523,7 +516,7 @@ in rec {
     extraAttrs = {
       libc = pkgs.darwin.Libsystem;
       shellPackage = pkgs.bash;
-      inherit macosVersionMin bootstrapTools;
+      inherit bootstrapTools;
     };
 
     allowedRequisites = (with pkgs; [

pkgs/stdenv/generic/default.nix

@@ -106,6 +106,8 @@ let
       '' + lib.optionalString (hostPlatform.isDarwin || (hostPlatform.parsed.kernel.execFormat != lib.systems.parse.execFormats.elf && hostPlatform.parsed.kernel.execFormat != lib.systems.parse.execFormats.macho)) ''
         export NIX_DONT_SET_RPATH=1
         export NIX_NO_SELF_RPATH=1
+      '' + lib.optionalString (hostPlatform.isDarwin && hostPlatform.isMacOS) ''
+        export MACOSX_DEPLOYMENT_TARGET=${hostPlatform.darwinMinVersion}
       ''
       # TODO this should be uncommented, but it causes stupid mass rebuilds. I
       # think the best solution would just be to fixup linux RPATHs so we don't