Fix clang tooling build on Linux (shim CMake in LLVM tree).

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=217949
 
 THIS_DIR="$(dirname "${0}")"
 LLVM_DIR="${THIS_DIR}/../../../third_party/llvm"
 LLVM_BUILD_DIR="${LLVM_DIR}/../llvm-build/Release+Asserts"
 COMPILER_RT_BUILD_DIR="${LLVM_DIR}/../llvm-build/compiler-rt"
 LLVM_BOOTSTRAP_DIR="${LLVM_DIR}/../llvm-bootstrap"
 LLVM_BOOTSTRAP_INSTALL_DIR="${LLVM_DIR}/../llvm-bootstrap-install"
 CLANG_DIR="${LLVM_DIR}/tools/clang"
 COMPILER_RT_DIR="${LLVM_DIR}/compiler-rt"
 LIBCXX_DIR="${LLVM_DIR}/projects/libcxx"
 LIBCXXABI_DIR="${LLVM_DIR}/projects/libcxxabi"
 ANDROID_NDK_DIR="${THIS_DIR}/../../../third_party/android_tools/ndk"
 STAMP_FILE="${LLVM_DIR}/../llvm-build/cr_build_revision"
+CHROMIUM_TOOLS_DIR="${THIS_DIR}/.."
 
+ABS_CHROMIUM_TOOLS_DIR="${PWD}/${CHROMIUM_TOOLS_DIR}"
 ABS_LIBCXX_DIR="${PWD}/${LIBCXX_DIR}"
 ABS_LIBCXXABI_DIR="${PWD}/${LIBCXXABI_DIR}"
 ABS_LLVM_DIR="${PWD}/${LLVM_DIR}"
 ABS_LLVM_BUILD_DIR="${PWD}/${LLVM_BUILD_DIR}"
 ABS_COMPILER_RT_DIR="${PWD}/${COMPILER_RT_DIR}"
 
 
 # Use both the clang revision and the plugin revisions to test for updates.
 BLINKGCPLUGIN_REVISION=\
 $(grep 'set(LIBRARYNAME' "$THIS_DIR"/../blink_gc_plugin/CMakeLists.txt \
@@ skipping 387 matching lines @@
     -nodefaultlibs -current_version 1 -compatibility_version 1 \
     -lSystem -install_name @executable_path/libc++.dylib \
     -Wl,-unexported_symbols_list,${ABS_LIBCXX_DIR}/lib/libc++unexp.exp \
     -Wl,-force_symbols_not_weak_list,${ABS_LIBCXX_DIR}/lib/notweak.exp \
     -Wl,-force_symbols_weak_list,${ABS_LIBCXX_DIR}/lib/weak.exp
   ln -sf libc++.1.dylib libc++.dylib
   popd
   LDFLAGS+="-stdlib=libc++ -L${PWD}/libcxxbuild"
 fi
 
+# Hook the Chromium tools into the LLVM build. Several Chromium tools have
+# dependencies on LLVM/Clang libraries. The LLVM build detects implicit tools
+# in the tools subdirectory, so install a shim CMakeLists.txt that forwards to
+# the real directory for the Chromium tools.
+# Note that the shim directory name intentionally has no _ or _. The implicit
+# tool detection logic munges them in a weird way.
+CHROME_TOOLS_SHIM_DIR=${ABS_LLVM_DIR}/tools/chrometools

[hans, 2014/10/03 01:23:45]

Why aren't we inserting the shim under tools/clang/tools/extra/ ? That's where I
thought it would be spontaneously.

[dcheng, 2014/10/03 03:47:51]

There's only one call to add_llvm_implicit_external_projects(), and it happens
in llvm/tools/CMakeLists.txt =/

[hans, 2014/10/03 17:07:14]

OK. Let's keep it here, then.

+rm -rfv ${CHROME_TOOLS_SHIM_DIR}
+mkdir -v ${CHROME_TOOLS_SHIM_DIR}
+cat > ${CHROME_TOOLS_SHIM_DIR}/CMakeLists.txt << EOF
+# Since tools/clang isn't actually a subdirectory, use the two argument version
+# to specify where build artifacts go. CMake doesn't allow reusing the same
+# binary dir for multiple source dirs, so the build artifacts have to go into a
+# subdirectory...
+add_subdirectory(\${CHROMIUM_TOOLS_SRC} \${CMAKE_CURRENT_BINARY_DIR}/a)
+EOF
 rm -fv CMakeCache.txt
 MACOSX_DEPLOYMENT_TARGET=${deployment_target} cmake -GNinja \
     -DCMAKE_BUILD_TYPE=Release \
     -DLLVM_ENABLE_ASSERTIONS=ON \
     -DLLVM_ENABLE_THREADS=OFF \
     -DCMAKE_C_COMPILER="${CC}" \
     -DCMAKE_CXX_COMPILER="${CXX}" \
     -DCMAKE_C_FLAGS="${CFLAGS}" \
     -DCMAKE_CXX_FLAGS="${CXXFLAGS}" \
     -DCMAKE_EXE_LINKER_FLAGS="${LDFLAGS}" \
     -DCMAKE_SHARED_LINKER_FLAGS="${LDFLAGS}" \
     -DCMAKE_MODULE_LINKER_FLAGS="${LDFLAGS}" \
+    -DCMAKE_INSTALL_PREFIX="${ABS_LLVM_BUILD_DIR}" \
+    -DCHROMIUM_TOOLS_SRC="${ABS_CHROMIUM_TOOLS_DIR}" \
+    -DCHROMIUM_TOOLS="${chrome_tools}" \
     "${ABS_LLVM_DIR}"
 env
 
 if [[ -n "${gcc_toolchain}" ]]; then
   # Copy in the right stdlibc++.so.6 so clang can start.
   mkdir -p lib
   cp -v "$(${CXX} ${CXXFLAGS} -print-file-name=libstdc++.so.6)" lib/
 fi
 
 ninja
+# If any Chromium tools were built, install those now.
+if [[ -n "${chrome_tools}" ]]; then
+  ninja cr-install
+fi
 
 STRIP_FLAGS=
 if [ "${OS}" = "Darwin" ]; then
   # See http://crbug.com/256342
   STRIP_FLAGS=-x
 
   cp libcxxbuild/libc++.1.dylib bin/
 fi
 strip ${STRIP_FLAGS} bin/clang
 popd
@@ skipping 56 matching lines @@
       -DCMAKE_CXX_FLAGS="--target=arm-linux-androideabi --sysroot=${PWD}/../android-toolchain/sysroot -B${PWD}/../android-toolchain" \
       -DANDROID=1 \
       "${ABS_COMPILER_RT_DIR}"
   ninja clang_rt.asan-arm-android
 
   # And copy it into the main build tree.
   cp "$(find -name libclang_rt.asan-arm-android.so)" "${ABS_LLVM_CLANG_LIB_DIR}/lib/linux/"
   popd
 fi
 
-# Build Chrome-specific clang tools. Paths in this list should be relative to
-# tools/clang.
-TOOL_SRC_DIR="${PWD}/${THIS_DIR}/../"
-TOOL_BUILD_DIR="${ABS_LLVM_BUILD_DIR}/tools/clang/tools/chrome-extras"
-
-rm -rf "${TOOL_BUILD_DIR}"
-mkdir -p "${TOOL_BUILD_DIR}"
-pushd "${TOOL_BUILD_DIR}"
-rm -fv CMakeCache.txt
-MACOSX_DEPLOYMENT_TARGET=${deployment_target} cmake -GNinja  \
-    -DLLVM_BUILD_DIR="${ABS_LLVM_BUILD_DIR}" \
-    -DLLVM_SRC_DIR="${ABS_LLVM_DIR}" \
-    -DCMAKE_C_COMPILER="${CC}" \
-    -DCMAKE_CXX_COMPILER="${CXX}" \
-    -DCMAKE_C_FLAGS="${CFLAGS}" \
-    -DCMAKE_CXX_FLAGS="${CXXFLAGS}" \
-    -DCMAKE_EXE_LINKER_FLAGS="${LDFLAGS}" \
-    -DCMAKE_SHARED_LINKER_FLAGS="${LDFLAGS}" \
-    -DCMAKE_MODULE_LINKER_FLAGS="${LDFLAGS}" \
-    -DCMAKE_INSTALL_PREFIX="${ABS_LLVM_BUILD_DIR}" \
-    -DCHROMIUM_TOOLS="${chrome_tools}" \
-    "${TOOL_SRC_DIR}"
-popd
-ninja -C "${TOOL_BUILD_DIR}" install
-
 if [[ -n "$run_tests" ]]; then
   # Run Chrome tool tests.
-  ninja -C "${TOOL_BUILD_DIR}" check-all
+  ninja -C "${LLVM_BUILD_DIR}" cr-check-all
   # Run the LLVM and Clang tests.
   ninja -C "${LLVM_BUILD_DIR}" check-all
 fi
 
 # After everything is done, log success for this revision.
 echo "${CLANG_AND_PLUGINS_REVISION}" > "${STAMP_FILE}"