[CMake] Use ExternalProject to build MSan-ified version of libcxx for unit tests.

This change lets MSan rely on libcxx's own build system instead of manually
compiling its sources and setting up all the necessary compile flags. It would
also simplify compiling libcxx with another sanitizers (in particular, TSan).

The tricky part is to make sure libcxx is reconfigured/rebuilt when Clang or
MSan runtime library is changed. "clobber" step used in this patch works well
for me, but it's possible it would break for other configurations - will
watch the buildbots.


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@208451 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 22 insertions, 53 deletions

diff --git a/lib/msan/tests/CMakeLists.txt b/lib/msan/tests/CMakeLists.txt
index cc58d2e1e..c65461517 100644
--- a/lib/msan/tests/CMakeLists.txt
+++ b/lib/msan/tests/CMakeLists.txt
@@ -5,29 +5,10 @@ include(CompilerRTLink)
 include_directories(..)
 include_directories(../..)
 
-# Instrumented libcxx sources and build flags.
-file(GLOB MSAN_LIBCXX_SOURCES ${COMPILER_RT_LIBCXX_PATH}/src/*.cpp)
 set(MSAN_LIBCXX_CFLAGS
-  -I${COMPILER_RT_LIBCXX_PATH}/include
   -fsanitize=memory
   -fsanitize-memory-track-origins
-  -fPIC
-  -Wno-\#warnings
-  -Wno-pedantic
-  -g
-  -O2
-  -fstrict-aliasing
-  -fno-exceptions
-  -nostdinc++
-  -fno-omit-frame-pointer
-  -mno-omit-leaf-frame-pointer)
-set(MSAN_LIBCXX_LINK_FLAGS
-  -nodefaultlibs
-  -lrt
-  -lc
-  -lstdc++
-  -fsanitize=memory)
-append_if(COMPILER_RT_HAS_LIBPTHREAD -lpthread MSAN_LIBCXX_LINK_FLAGS)
+  -Wno-pedantic)
 
 # Unittest sources and build flags.
 set(MSAN_UNITTEST_SOURCES msan_test.cc msan_test_main.cc)
@@ -103,46 +84,23 @@ macro(msan_link_shared so_list so_name arch kind)
   list(APPEND ${so_list} ${output_so})
 endmacro()
 
-# Link MSan unit test for a given architecture from a set
-# of objects in ${ARGN}.
-macro(add_msan_test test_suite test_name arch)
-  get_target_flags_for_arch(${arch} TARGET_LINK_FLAGS)
-  set(TEST_DEPS ${ARGN} ${MSAN_LOADABLE_SO})
-  if(NOT COMPILER_RT_STANDALONE_BUILD)
-    list(APPEND TEST_DEPS msan)
-  endif()
-  add_compiler_rt_test(${test_suite} ${test_name}
-                       OBJECTS ${ARGN}
-                       DEPS ${TEST_DEPS}
-                       LINK_FLAGS ${MSAN_UNITTEST_LINK_FLAGS}
-                                  ${TARGET_LINK_FLAGS}
-                                  "-Wl,-rpath=${CMAKE_CURRENT_BINARY_DIR}")
-endmacro()
-
 # Main MemorySanitizer unit tests.
 add_custom_target(MsanUnitTests)
 set_target_properties(MsanUnitTests PROPERTIES FOLDER "MSan unit tests")
 
 # Adds MSan unit tests and benchmarks for architecture.
 macro(add_msan_tests_for_arch arch kind)
+  set(LIBCXX_PREFIX ${CMAKE_CURRENT_BINARY_DIR}/../libcxx_msan${kind})
+  add_custom_libcxx(libcxx_msan${kind} ${LIBCXX_PREFIX}
+    DEPS ${MSAN_RUNTIME_LIBRARIES}
+    CFLAGS ${MSAN_LIBCXX_CFLAGS} ${ARGN})
+  set(MSAN_LIBCXX_SO ${LIBCXX_PREFIX}/lib/libc++.so)
+
   # Build gtest instrumented with MSan.
   set(MSAN_INST_GTEST)
   msan_compile(MSAN_INST_GTEST ${COMPILER_RT_GTEST_SOURCE} ${arch} "${kind}"
                                ${MSAN_UNITTEST_INSTRUMENTED_CFLAGS} ${ARGN})
 
-  # Build libcxx instrumented with MSan.
-  set(MSAN_INST_LIBCXX_OBJECTS)
-  foreach(SOURCE ${MSAN_LIBCXX_SOURCES})
-    msan_compile(MSAN_INST_LIBCXX_OBJECTS ${SOURCE} ${arch} "${kind}"
-                 ${MSAN_LIBCXX_CFLAGS} ${ARGN})
-  endforeach(SOURCE)
-
-  set(MSAN_INST_LIBCXX)
-  msan_link_shared(MSAN_INST_LIBCXX "libcxx" ${arch} "${kind}"
-                   OBJECTS ${MSAN_INST_LIBCXX_OBJECTS}
-                   LINKFLAGS ${MSAN_LIBCXX_LINK_FLAGS}
-                   DEPS ${MSAN_INST_LIBCXX_OBJECTS})
-
   # Instrumented tests.
   set(MSAN_INST_TEST_OBJECTS)
   foreach (SOURCE ${MSAN_UNITTEST_SOURCES})
@@ -172,10 +130,21 @@ macro(add_msan_tests_for_arch arch kind)
                    OBJECTS ${MSANDR_TEST_OBJECTS}
                    DEPS ${MSANDR_TEST_OBJECTS})
 
-  # Link everything together.
-  add_msan_test(MsanUnitTests "Msan-${arch}${kind}-Test" ${arch}
-                ${MSAN_INST_TEST_OBJECTS} ${MSAN_INST_GTEST}
-                ${MSAN_INST_LIBCXX} ${MSANDR_TEST_SO})
+  set(MSAN_TEST_OBJECTS ${MSAN_INST_TEST_OBJECTS} ${MSAN_INST_GTEST}
+                        ${MSANDR_TEST_SO})
+  set(MSAN_TEST_DEPS ${MSAN_TEST_OBJECTS} libcxx_msan${kind}
+                     ${MSAN_LOADABLE_SO})
+  if(NOT COMPILER_RT_STANDALONE_BUILD)
+    list(APPEND MSAN_TEST_DEPS msan)
+  endif()
+  get_target_flags_for_arch(${arch} TARGET_LINK_FLAGS)
+  add_compiler_rt_test(MsanUnitTests "Msan-${arch}${kind}-Test" ${arch}
+	  OBJECTS ${MSAN_TEST_OBJECTS} ${MSAN_LIBCXX_SO}
+	  DEPS ${MSAN_TEST_DEPS}
+	  LINK_FLAGS ${MSAN_UNITTEST_LINK_FLAGS}
+                     ${TARGET_LINK_FLAGS}
+                     "-Wl,-rpath=${CMAKE_CURRENT_BINARY_DIR}"
+                     "-Wl,-rpath=${LIBCXX_PREFIX}/lib")
 endmacro()
 
 # We should only build MSan unit tests if we can build instrumented libcxx.