From aac819b84442a57e573e2d87d8903e820e0bee1a Mon Sep 17 00:00:00 2001 From: Petr Hosek Date: Sat, 9 Mar 2019 01:26:55 +0000 Subject: [PATCH] [CMake] Support stripping and linking output to .build-id directory When installing runtimes with install-runtimes-stripped, we don't want to just strip them, we also want to preserve the debugging information for potential debugging. To make it possible to later find the stripped debugging information, we want to use the .build-id layout: https://fedoraproject.org/wiki/RolandMcGrath/BuildID#Find_files_by_build_ID That is, for libfoo.so with build ID abcdef1234, the debugging information will be installed into lib/debug/.build-id/ab/cdef1234. llvm-objcopy already has support for stripping files and linking the debugging stripped output into the right location. However, CMake doesn't support customizing strip invocation for the *-stripped targets. So instead, we replace CMAKE_STRIP with a custom script that invokes llvm-objcopy with the right command line flags. Differential Revision: https://reviews.llvm.org/D59127 llvm-svn: 355765 --- clang/cmake/caches/Fuchsia-stage2.cmake | 7 ++++++ llvm/cmake/modules/LLVMExternalProjectUtils.cmake | 10 +++++++-- llvm/runtimes/CMakeLists.txt | 12 ++++++++++ llvm/runtimes/llvm-strip-link.in | 27 +++++++++++++++++++++++ 4 files changed, 54 insertions(+), 2 deletions(-) create mode 100755 llvm/runtimes/llvm-strip-link.in diff --git a/clang/cmake/caches/Fuchsia-stage2.cmake b/clang/cmake/caches/Fuchsia-stage2.cmake index 51efb2d..fab7f0d 100644 --- a/clang/cmake/caches/Fuchsia-stage2.cmake +++ b/clang/cmake/caches/Fuchsia-stage2.cmake @@ -74,6 +74,9 @@ foreach(target aarch64-linux-gnu;armv7-linux-gnueabihf;i386-linux-gnu;x86_64-lin set(RUNTIMES_${target}_SANITIZER_CXX_ABI "libc++" CACHE STRING "") set(RUNTIMES_${target}_SANITIZER_CXX_ABI_INTREE ON CACHE BOOL "") set(RUNTIMES_${target}_COMPILER_RT_USE_BUILTINS_LIBRARY ON CACHE BOOL "") + + # Use .build-id link. + list(APPEND RUNTIME_BUILD_ID_LINK "${target}") endif() endforeach() @@ -126,6 +129,9 @@ if(FUCHSIA_SDK) set(RUNTIMES_${target}-fuchsia_LIBCXX_HERMETIC_STATIC_LIBRARY ON CACHE BOOL "") set(RUNTIMES_${target}-fuchsia_LIBCXX_STATICALLY_LINK_ABI_IN_SHARED_LIBRARY OFF CACHE BOOL "") set(RUNTIMES_${target}-fuchsia_LIBCXX_ABI_VERSION 2 CACHE STRING "") + + # Use .build-id link. + list(APPEND RUNTIME_BUILD_ID_LINK "${target}-fuchsia") endforeach() set(LLVM_RUNTIME_SANITIZERS "Address" CACHE STRING "") @@ -134,6 +140,7 @@ endif() set(LLVM_BUILTIN_TARGETS "${BUILTIN_TARGETS}" CACHE STRING "") set(LLVM_RUNTIME_TARGETS "${RUNTIME_TARGETS}" CACHE STRING "") +set(LLVM_RUNTIME_BUILD_ID_LINK_TARGETS "${RUNTIME_BUILD_ID_LINK}" CACHE STRING "") # Setup toolchain. set(LLVM_INSTALL_TOOLCHAIN_ONLY ON CACHE BOOL "") diff --git a/llvm/cmake/modules/LLVMExternalProjectUtils.cmake b/llvm/cmake/modules/LLVMExternalProjectUtils.cmake index 4d26a30..dab7182 100644 --- a/llvm/cmake/modules/LLVMExternalProjectUtils.cmake +++ b/llvm/cmake/modules/LLVMExternalProjectUtils.cmake @@ -35,12 +35,14 @@ endfunction() # Extra targets in the subproject to generate targets for # PASSTHROUGH_PREFIXES prefix... # Extra variable prefixes (name is always included) to pass down +# STRIP_TOOL path +# Use provided strip tool instead of the default one. # ) function(llvm_ExternalProject_Add name source_dir) cmake_parse_arguments(ARG "USE_TOOLCHAIN;EXCLUDE_FROM_ALL;NO_INSTALL;ALWAYS_CLEAN" "SOURCE_DIR" - "CMAKE_ARGS;TOOLCHAIN_TOOLS;RUNTIME_LIBRARIES;DEPENDS;EXTRA_TARGETS;PASSTHROUGH_PREFIXES" + "CMAKE_ARGS;TOOLCHAIN_TOOLS;RUNTIME_LIBRARIES;DEPENDS;EXTRA_TARGETS;PASSTHROUGH_PREFIXES;STRIP_TOOL" ${ARGN}) canonicalize_tool_name(${name} nameCanon) if(NOT ARG_TOOLCHAIN_TOOLS) @@ -125,12 +127,16 @@ function(llvm_ExternalProject_Add name source_dir) if(llvm-objcopy IN_LIST TOOLCHAIN_TOOLS) list(APPEND compiler_args -DCMAKE_OBJCOPY=${LLVM_RUNTIME_OUTPUT_INTDIR}/llvm-objcopy) endif() - if(llvm-strip IN_LIST TOOLCHAIN_TOOLS) + if(llvm-strip IN_LIST TOOLCHAIN_TOOLS AND NOT ARG_STRIP_TOOL) list(APPEND compiler_args -DCMAKE_STRIP=${LLVM_RUNTIME_OUTPUT_INTDIR}/llvm-strip) endif() list(APPEND ARG_DEPENDS ${TOOLCHAIN_TOOLS}) endif() + if(ARG_STRIP_TOOL) + list(APPEND compiler_args -DCMAKE_STRIP=${ARG_STRIP_TOOL}) + endif() + add_custom_command( OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/${name}-clobber-stamp DEPENDS ${ARG_DEPENDS} diff --git a/llvm/runtimes/CMakeLists.txt b/llvm/runtimes/CMakeLists.txt index 4cb3ed9..1866b256 100644 --- a/llvm/runtimes/CMakeLists.txt +++ b/llvm/runtimes/CMakeLists.txt @@ -318,6 +318,14 @@ else() # if this is included from LLVM's CMake list(APPEND runtime_names ${projName}) endforeach() + if(LLVM_RUNTIME_BUILD_ID_LINK_TARGETS) + configure_file( + ${CMAKE_CURRENT_SOURCE_DIR}/llvm-strip-link.in + ${CMAKE_CURRENT_BINARY_DIR}/llvm-strip-link + @ONLY + ) + endif() + function(runtime_default_target) cmake_parse_arguments(ARG "" "" "DEPENDS;PREFIXES" ${ARGN}) @@ -426,6 +434,10 @@ else() # if this is included from LLVM's CMake endif() endforeach() + if(target IN_LIST LLVM_RUNTIME_BUILD_ID_LINK_TARGETS) + list(APPEND EXTRA_ARGS STRIP_TOOL ${CMAKE_CURRENT_BINARY_DIR}/llvm-strip-link) + endif() + llvm_ExternalProject_Add(runtimes-${name} ${CMAKE_CURRENT_SOURCE_DIR} DEPENDS ${${name}_deps} diff --git a/llvm/runtimes/llvm-strip-link.in b/llvm/runtimes/llvm-strip-link.in new file mode 100755 index 0000000..f9f6a98 --- /dev/null +++ b/llvm/runtimes/llvm-strip-link.in @@ -0,0 +1,27 @@ +#!/usr/bin/env python +# -*- coding: utf-8 -*- + +import os +import sys +import subprocess + + +ELF_MAGIC = '\x7fELF' + +with open(sys.argv[1], "rb") as f: + buf = f.read(len(ELF_MAGIC)) + if buf != ELF_MAGIC: + sys.exit(0) + +llvm_objcopy = os.path.join('@LLVM_RUNTIME_OUTPUT_INTDIR@', 'llvm-objcopy') +install_dir = os.path.join(os.getenv('DESTDIR', ''), '@CMAKE_INSTALL_PREFIX@') +link_dir = os.path.join(install_dir, 'lib', 'debug', '.build-id') + +sys.exit(subprocess.call([ + llvm_objcopy, + '--strip-sections', + '--build-id-link-dir=' + link_dir, + '--build-id-link-input=.debug', + '--build-id-link-output=', + sys.argv[1], +])) -- 2.7.4