When building Clang for Mac, make LC_ID_DYLIB of the ASan dynamic runtime to be relative to @execut…

tools/clang/scripts/package.sh

 #!/bin/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, and then package the results up
 # to a tgz file.
 
 THIS_DIR="$(dirname "${0}")"
 LLVM_DIR="${THIS_DIR}/../../../third_party/llvm"
@@ skipping 46 matching lines @@
 else
   cp "${LLVM_LIB_DIR}/libFindBadConstructs.so" $PDIR/lib
 fi
 
 # Copy built-in headers (lib/clang/3.2/include).
 # libcompiler-rt puts all kinds of libraries there too, but we want only ASan.
 if [ "$(uname -s)" = "Darwin" ]; then
   # Keep only Release+Asserts/lib/clang/3.2/lib/darwin/libclang_rt.asan_osx.a
   find "${LLVM_LIB_DIR}/clang" -type f -path '*lib/darwin*' | grep -v asan | \
        xargs rm
+  # Fix LC_ID_DYLIB for the ASan dynamic library to be relative to
+  # @executable_path.
+  # TODO(glider): this is transitional. We'll need to fix the dylib name
+  # either in our build system, or in Clang. See also http://crbug.com/170629.
+  ASAN_DYLIB_NAME=libclang_rt.asan_osx_dynamic.dylib
+  ASAN_DYLIB=$(find "${LLVM_LIB_DIR}/clang" -type f -path "*${ASAN_DYLIB_NAME}")
+  install_name_tool -id @executable_path/${ASAN_DYLIB_NAME} "${ASAN_DYLIB}"
 else
   # Keep only
   # Release+Asserts/lib/clang/3.2/lib/linux/libclang_rt.{asan,tsan}-x86_64.a
   # TODO(thakis): Make sure the 32bit version of ASan runtime is kept too once
   # that's built. TSan runtime exists only for 64 bits.
   find "${LLVM_LIB_DIR}/clang" -type f -path '*lib/linux*' | \
        grep -v "asan\|tsan" | xargs rm
 fi
 
 cp -R "${LLVM_LIB_DIR}/clang" $PDIR/lib
 
 tar zcf $PDIR.tgz -C $PDIR bin lib buildlog.txt
 
 if [ "$(uname -s)" = "Darwin" ]; then
   PLATFORM=Mac
 else
   PLATFORM=Linux_x64
 fi
 
 echo To upload, run:
 echo gsutil cp -a public-read $PDIR.tgz \
      gs://chromium-browser-clang/$PLATFORM/$PDIR.tgz