Pin Clang revision to r170392 for ASan Mac builders.

tools/clang/scripts/update.sh

 #!/usr/bin/env bash
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # This script will check out llvm and clang into third_party/llvm and build it.
 
 # Do NOT CHANGE this if you don't know what you're doing -- see
 # https://code.google.com/p/chromium/wiki/UpdatingClang
 # Reverting problematic clang rolls is safe, though.
 CLANG_REVISION=170392
+# ASan Mac builders are pinned to this revision, see http://crbug.com/170629.
+CLANG_ASAN_MAC_REVISION=170392
 
 THIS_DIR="$(dirname "${0}")"
 LLVM_DIR="${THIS_DIR}/../../../third_party/llvm"
 LLVM_BUILD_DIR="${LLVM_DIR}/../llvm-build"
 LLVM_BOOTSTRAP_DIR="${LLVM_DIR}/../llvm-bootstrap"
 CLANG_DIR="${LLVM_DIR}/tools/clang"
 COMPILER_RT_DIR="${LLVM_DIR}/projects/compiler-rt"
 ANDROID_NDK_DIR="${LLVM_DIR}/../android_tools/ndk"
 STAMP_FILE="${LLVM_BUILD_DIR}/cr_build_revision"
 
 # ${A:-a} returns $A if it's set, a else.
 LLVM_REPO_URL=${LLVM_URL:-https://llvm.org/svn/llvm-project}
 
 # Die if any command dies.
 set -e
 
 OS="$(uname -s)"
 
 # Parse command line options.
 force_local_build=
 mac_only=
 run_tests=
 bootstrap=
 with_android=yes
+is_asan_mac_builder=
 if [[ "${OS}" = "Darwin" ]]; then
   with_android=
 fi
 
 while [[ $# > 0 ]]; do
   case $1 in
     --bootstrap)
       bootstrap=yes
       ;;
     --force-local-build)
       force_local_build=yes
       ;;
     --mac-only)
       mac_only=yes
       ;;
     --run-tests)
       run_tests=yes
       ;;
     --without-android)
       with_android=
       ;;
+    --is-asan-mac-builder)
+      is_asan_mac_builder=yes

[Nico, 2013/02/12 16:51:25]

This is in already, but in the future when doing something like this please

a) Add a comment that calls this out as a temporary workaround. There's a
comment with a link to a bug below, but it's hidden and it's not obvious from
the code that this is temporary.

b) Make the UI so that it's obvious that is temporary. In this case, you could
call the flag "--asan-mac-builder-hackfix" or similar.

+      ;;
     --help)
       echo "usage: $0 [--force-local-build] [--mac-only] [--run-tests] "
       echo "--bootstrap: First build clang with CC, then with itself."
       echo "--force-local-build: Don't try to download prebuilt binaries."
       echo "--mac-only: Do initial download only on Mac systems."
       echo "--run-tests: Run tests after building. Only for local builds."
       echo "--without-android: Don't build ASan Android runtime library."
+      echo "--is-asan-mac-builder: Use older Clang to build ASan on Mac."
       exit 1
       ;;
   esac
   shift
 done
 
+# Are we on a Chrome buildbot running ASan?
+function on_asan_mac_host {
+  HOST="$(uname -n)"
+  if [[ "${HOST}" == "vm633-m1.golo.chromium.org" ]]; then
+    return 0
+  fi
+  for num in $(seq 600 655)
+  do
+    if [[ "${HOST}" == "vm${num}-m4.golo.chromium.org" ]]; then
+      return 0
+    fi
+  done
+  return 1
+}
+
+# Use older Clang for ASan Mac builds. See http://crbug.com/170629.
+if [[ -n is_asan_mac_builder ]] || on_asan_mac_host; then
+  CLANG_REVISION=${CLANG_ASAN_MAC_REVISION}
+fi
+
 # --mac-only prevents the initial download on non-mac systems, but if clang has
 # already been downloaded in the past, this script keeps it up to date even if
 # --mac-only is passed in and the system isn't a mac. People who don't like this
 # can just delete their third_party/llvm-build directory.
 if [[ -n "$mac_only" ]] && [[ "${OS}" != "Darwin" ]] &&
     [[ ! ( "$GYP_DEFINES" =~ .*(clang|tsan|asan)=1.* ) ]] &&
     ! [[ -d "${LLVM_BUILD_DIR}" ]]; then
   exit 0
 fi
 
@@ skipping 249 matching lines @@
 if [[ -n "$run_tests" ]]; then
   # Run a few tests.
   "${PLUGIN_SRC_DIR}/tests/test.sh" "${LLVM_BUILD_DIR}/Release+Asserts"
   cd "${LLVM_BUILD_DIR}"
   make check-all
   cd -
 fi
 
 # After everything is done, log success for this revision.
 echo "${CLANG_REVISION}" > "${STAMP_FILE}"