diff --git a/infra/recipes/gn.expected/cq_mac.json b/infra/recipes/gn.expected/cq_mac.json
index 9eccbfe..64234cc 100644
--- a/infra/recipes/gn.expected/cq_mac.json
+++ b/infra/recipes/gn.expected/cq_mac.json
@@ -102,17 +102,6 @@
     ]
   },
   {
-    "cmd": [],
-    "name": "debug"
-  },
-  {
-    "cmd": [],
-    "name": "debug.build",
-    "~followup_annotations": [
-      "@@@STEP_NEST_LEVEL@1@@@"
-    ]
-  },
-  {
     "cmd": [
       "cipd",
       "ensure",
@@ -123,17 +112,9 @@
       "-json-output",
       "/path/to/tmp/json"
     ],
-    "cwd": "[START_DIR]/gn",
-    "env": {
-      "AR": "[START_DIR]/cipd/bin/llvm-ar",
-      "CC": "[START_DIR]/cipd/bin/clang",
-      "CXX": "[START_DIR]/cipd/bin/clang++",
-      "LDFLAGS": "-nostdlib++ [START_DIR]/cipd/lib/libc++.a [START_DIR]/cipd/lib/libc++abi.a [START_DIR]/cipd/lib/libunwind.a"
-    },
     "infra_step": true,
-    "name": "debug.build.ensure_installed",
+    "name": "ensure_installed (2)",
     "~followup_annotations": [
-      "@@@STEP_NEST_LEVEL@2@@@",
       "@@@STEP_LOG_LINE@json.output@{@@@",
       "@@@STEP_LOG_LINE@json.output@  \"result\": {@@@",
       "@@@STEP_LOG_LINE@json.output@    \"\": [@@@",
@@ -158,18 +139,8 @@
       "-output-dir",
       "[CACHE]/macos_sdk/XCode.app"
     ],
-    "cwd": "[START_DIR]/gn",
-    "env": {
-      "AR": "[START_DIR]/cipd/bin/llvm-ar",
-      "CC": "[START_DIR]/cipd/bin/clang",
-      "CXX": "[START_DIR]/cipd/bin/clang++",
-      "LDFLAGS": "-nostdlib++ [START_DIR]/cipd/lib/libc++.a [START_DIR]/cipd/lib/libc++abi.a [START_DIR]/cipd/lib/libunwind.a"
-    },
     "infra_step": true,
-    "name": "debug.build.install xcode",
-    "~followup_annotations": [
-      "@@@STEP_NEST_LEVEL@2@@@"
-    ]
+    "name": "install xcode"
   },
   {
     "cmd": [
@@ -178,17 +149,30 @@
       "--switch",
       "[CACHE]/macos_sdk/XCode.app"
     ],
-    "cwd": "[START_DIR]/gn",
-    "env": {
-      "AR": "[START_DIR]/cipd/bin/llvm-ar",
-      "CC": "[START_DIR]/cipd/bin/clang",
-      "CXX": "[START_DIR]/cipd/bin/clang++",
-      "LDFLAGS": "-nostdlib++ [START_DIR]/cipd/lib/libc++.a [START_DIR]/cipd/lib/libc++abi.a [START_DIR]/cipd/lib/libunwind.a"
-    },
     "infra_step": true,
-    "name": "debug.build.select XCode",
+    "name": "select XCode"
+  },
+  {
+    "cmd": [
+      "xcrun",
+      "--show-sdk-path"
+    ],
+    "name": "xcrun",
+    "stdout": "/path/to/tmp/",
     "~followup_annotations": [
-      "@@@STEP_NEST_LEVEL@2@@@"
+      "@@@STEP_LOG_LINE@raw_io.output[sdk-path]@/some/xcode/path@@@",
+      "@@@STEP_LOG_END@raw_io.output[sdk-path]@@@"
+    ]
+  },
+  {
+    "cmd": [],
+    "name": "debug"
+  },
+  {
+    "cmd": [],
+    "name": "debug.build",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
     ]
   },
   {
@@ -202,8 +186,9 @@
     "env": {
       "AR": "[START_DIR]/cipd/bin/llvm-ar",
       "CC": "[START_DIR]/cipd/bin/clang",
+      "CFLAGS": "--sysroot=/some/xcode/path",
       "CXX": "[START_DIR]/cipd/bin/clang++",
-      "LDFLAGS": "-nostdlib++ [START_DIR]/cipd/lib/libc++.a [START_DIR]/cipd/lib/libc++abi.a [START_DIR]/cipd/lib/libunwind.a"
+      "LDFLAGS": "--sysroot=/some/xcode/path -nostdlib++ [START_DIR]/cipd/lib/libc++.a [START_DIR]/cipd/lib/libc++abi.a [START_DIR]/cipd/lib/libunwind.a"
     },
     "name": "debug.build.generate",
     "~followup_annotations": [
@@ -220,8 +205,9 @@
     "env": {
       "AR": "[START_DIR]/cipd/bin/llvm-ar",
       "CC": "[START_DIR]/cipd/bin/clang",
+      "CFLAGS": "--sysroot=/some/xcode/path",
       "CXX": "[START_DIR]/cipd/bin/clang++",
-      "LDFLAGS": "-nostdlib++ [START_DIR]/cipd/lib/libc++.a [START_DIR]/cipd/lib/libc++abi.a [START_DIR]/cipd/lib/libunwind.a"
+      "LDFLAGS": "--sysroot=/some/xcode/path -nostdlib++ [START_DIR]/cipd/lib/libc++.a [START_DIR]/cipd/lib/libc++abi.a [START_DIR]/cipd/lib/libunwind.a"
     },
     "name": "debug.build.ninja",
     "~followup_annotations": [
@@ -230,25 +216,6 @@
   },
   {
     "cmd": [
-      "sudo",
-      "xcode-select",
-      "--reset"
-    ],
-    "cwd": "[START_DIR]/gn",
-    "env": {
-      "AR": "[START_DIR]/cipd/bin/llvm-ar",
-      "CC": "[START_DIR]/cipd/bin/clang",
-      "CXX": "[START_DIR]/cipd/bin/clang++",
-      "LDFLAGS": "-nostdlib++ [START_DIR]/cipd/lib/libc++.a [START_DIR]/cipd/lib/libc++abi.a [START_DIR]/cipd/lib/libunwind.a"
-    },
-    "infra_step": true,
-    "name": "debug.build.reset XCode",
-    "~followup_annotations": [
-      "@@@STEP_NEST_LEVEL@2@@@"
-    ]
-  },
-  {
-    "cmd": [
       "[START_DIR]/gn/out/gn_unittests"
     ],
     "name": "debug.test",
@@ -269,85 +236,6 @@
   },
   {
     "cmd": [
-      "cipd",
-      "ensure",
-      "-root",
-      "[CACHE]/macos_sdk",
-      "-ensure-file",
-      "infra/tools/mac_toolchain/${platform} git_revision:796d2b92cff93fc2059623ce0a66284373ceea0a",
-      "-json-output",
-      "/path/to/tmp/json"
-    ],
-    "cwd": "[START_DIR]/gn",
-    "env": {
-      "AR": "[START_DIR]/cipd/bin/llvm-ar",
-      "CC": "[START_DIR]/cipd/bin/clang",
-      "CXX": "[START_DIR]/cipd/bin/clang++",
-      "LDFLAGS": "-nostdlib++ [START_DIR]/cipd/lib/libc++.a [START_DIR]/cipd/lib/libc++abi.a [START_DIR]/cipd/lib/libunwind.a"
-    },
-    "infra_step": true,
-    "name": "release.build.ensure_installed",
-    "~followup_annotations": [
-      "@@@STEP_NEST_LEVEL@2@@@",
-      "@@@STEP_LOG_LINE@json.output@{@@@",
-      "@@@STEP_LOG_LINE@json.output@  \"result\": {@@@",
-      "@@@STEP_LOG_LINE@json.output@    \"\": [@@@",
-      "@@@STEP_LOG_LINE@json.output@      {@@@",
-      "@@@STEP_LOG_LINE@json.output@        \"instance_id\": \"resolved-instance_id-of-git_revision:796\", @@@",
-      "@@@STEP_LOG_LINE@json.output@        \"package\": \"infra/tools/mac_toolchain/${platform}\"@@@",
-      "@@@STEP_LOG_LINE@json.output@      }@@@",
-      "@@@STEP_LOG_LINE@json.output@    ]@@@",
-      "@@@STEP_LOG_LINE@json.output@  }@@@",
-      "@@@STEP_LOG_LINE@json.output@}@@@",
-      "@@@STEP_LOG_END@json.output@@@"
-    ]
-  },
-  {
-    "cmd": [
-      "[CACHE]/macos_sdk/mac_toolchain",
-      "install",
-      "-kind",
-      "mac",
-      "-xcode-version",
-      "9c40b",
-      "-output-dir",
-      "[CACHE]/macos_sdk/XCode.app"
-    ],
-    "cwd": "[START_DIR]/gn",
-    "env": {
-      "AR": "[START_DIR]/cipd/bin/llvm-ar",
-      "CC": "[START_DIR]/cipd/bin/clang",
-      "CXX": "[START_DIR]/cipd/bin/clang++",
-      "LDFLAGS": "-nostdlib++ [START_DIR]/cipd/lib/libc++.a [START_DIR]/cipd/lib/libc++abi.a [START_DIR]/cipd/lib/libunwind.a"
-    },
-    "infra_step": true,
-    "name": "release.build.install xcode",
-    "~followup_annotations": [
-      "@@@STEP_NEST_LEVEL@2@@@"
-    ]
-  },
-  {
-    "cmd": [
-      "sudo",
-      "xcode-select",
-      "--switch",
-      "[CACHE]/macos_sdk/XCode.app"
-    ],
-    "cwd": "[START_DIR]/gn",
-    "env": {
-      "AR": "[START_DIR]/cipd/bin/llvm-ar",
-      "CC": "[START_DIR]/cipd/bin/clang",
-      "CXX": "[START_DIR]/cipd/bin/clang++",
-      "LDFLAGS": "-nostdlib++ [START_DIR]/cipd/lib/libc++.a [START_DIR]/cipd/lib/libc++abi.a [START_DIR]/cipd/lib/libunwind.a"
-    },
-    "infra_step": true,
-    "name": "release.build.select XCode",
-    "~followup_annotations": [
-      "@@@STEP_NEST_LEVEL@2@@@"
-    ]
-  },
-  {
-    "cmd": [
       "python",
       "-u",
       "[START_DIR]/gn/build/gen.py"
@@ -356,8 +244,9 @@
     "env": {
       "AR": "[START_DIR]/cipd/bin/llvm-ar",
       "CC": "[START_DIR]/cipd/bin/clang",
+      "CFLAGS": "--sysroot=/some/xcode/path",
       "CXX": "[START_DIR]/cipd/bin/clang++",
-      "LDFLAGS": "-nostdlib++ [START_DIR]/cipd/lib/libc++.a [START_DIR]/cipd/lib/libc++abi.a [START_DIR]/cipd/lib/libunwind.a"
+      "LDFLAGS": "--sysroot=/some/xcode/path -nostdlib++ [START_DIR]/cipd/lib/libc++.a [START_DIR]/cipd/lib/libc++abi.a [START_DIR]/cipd/lib/libunwind.a"
     },
     "name": "release.build.generate",
     "~followup_annotations": [
@@ -374,8 +263,9 @@
     "env": {
       "AR": "[START_DIR]/cipd/bin/llvm-ar",
       "CC": "[START_DIR]/cipd/bin/clang",
+      "CFLAGS": "--sysroot=/some/xcode/path",
       "CXX": "[START_DIR]/cipd/bin/clang++",
-      "LDFLAGS": "-nostdlib++ [START_DIR]/cipd/lib/libc++.a [START_DIR]/cipd/lib/libc++abi.a [START_DIR]/cipd/lib/libunwind.a"
+      "LDFLAGS": "--sysroot=/some/xcode/path -nostdlib++ [START_DIR]/cipd/lib/libc++.a [START_DIR]/cipd/lib/libc++abi.a [START_DIR]/cipd/lib/libunwind.a"
     },
     "name": "release.build.ninja",
     "~followup_annotations": [
@@ -384,25 +274,6 @@
   },
   {
     "cmd": [
-      "sudo",
-      "xcode-select",
-      "--reset"
-    ],
-    "cwd": "[START_DIR]/gn",
-    "env": {
-      "AR": "[START_DIR]/cipd/bin/llvm-ar",
-      "CC": "[START_DIR]/cipd/bin/clang",
-      "CXX": "[START_DIR]/cipd/bin/clang++",
-      "LDFLAGS": "-nostdlib++ [START_DIR]/cipd/lib/libc++.a [START_DIR]/cipd/lib/libc++abi.a [START_DIR]/cipd/lib/libunwind.a"
-    },
-    "infra_step": true,
-    "name": "release.build.reset XCode",
-    "~followup_annotations": [
-      "@@@STEP_NEST_LEVEL@2@@@"
-    ]
-  },
-  {
-    "cmd": [
       "[START_DIR]/gn/out/gn_unittests"
     ],
     "name": "release.test",
@@ -411,6 +282,15 @@
     ]
   },
   {
+    "cmd": [
+      "sudo",
+      "xcode-select",
+      "--reset"
+    ],
+    "infra_step": true,
+    "name": "reset XCode"
+  },
+  {
     "name": "$result",
     "recipe_result": null,
     "status_code": 0