[msan] Blacklist __gxx_personality_v0.

[eugenis]

Summary

Fixes https://bugs.llvm.org/show_bug.cgi?id=31877.
Fixes https://github.com/google/sanitizers/issues/1155.

Enables exceptions in msan/tsan buid of libcxx, and in msan tests.

-fdepfile-entry stuff is a workaround for
https://reviews.llvm.org/D69290 (default blacklist missing from -MMD
output).

[eugenis]

remove an extra #include

compiler-rt/cmake/Modules/AddCompilerRT.cmake

CMAKE_ARGS ${CMAKE_PASSTHROUGH_VARIABLES}
                ${LIBCXX_CMAKE_ARGS}
     INSTALL_COMMAND ""
     STEP_TARGETS configure build
     BUILD_ALWAYS 1
     USES_TERMINAL_CONFIGURE 1
     USES_TERMINAL_BUILD 1
     USES_TERMINAL_INSTALL 1
     EXCLUDE_FROM_ALL TRUE
+    BUILD_BYPRODUCTS "${prefix}/lib/libc++.a" "${prefix}/lib/libc++abi.a"
     )
 
   if (CMAKE_GENERATOR MATCHES "Make")
     set(run_clean "$(MAKE)" "-C" "${BINARY_DIR}" "clean")
   else()
     set(run_clean ${CMAKE_COMMAND} --build ${BINARY_DIR} --target clean
                                    --config "$<CONFIG>")
   endif()

compiler-rt/cmake/Modules/CustomLibcxx/CMakeLists.txt

 cmake_minimum_required(VERSION 3.4.3)
 project(custom-libcxx C CXX)
 
 # Build static libcxxabi.
 set(LIBCXXABI_STANDALONE_BUILD 1)
 set(LIBCXXABI_ENABLE_SHARED OFF CACHE BOOL "")
-set(LIBCXXABI_ENABLE_EXCEPTIONS OFF CACHE BOOL "")
+set(LIBCXXABI_ENABLE_EXCEPTIONS ON CACHE BOOL "")
 set(LIBCXXABI_HERMETIC_STATIC_LIBRARY ON CACHE STRING "")
 set(LIBCXXABI_LIBCXX_PATH ${COMPILER_RT_LIBCXX_PATH} CACHE PATH "")
 set(LIBCXXABI_INCLUDE_TESTS OFF CACHE BOOL "")
 add_subdirectory(${COMPILER_RT_LIBCXXABI_PATH} ${CMAKE_CURRENT_BINARY_DIR}/cxxabi)
 
 # Build static libcxx without exceptions.
 set(LIBCXX_STANDALONE_BUILD 1)
 set(LIBCXX_ENABLE_EXPERIMENTAL_LIBRARY OFF CACHE BOOL "")

compiler-rt/lib/msan/CMakeLists.txt

add_sanitizer_rt_symbols(clang_rt.msan_cxx
       ARCHS ${arch}
       EXTRA msan.syms.extra)
     add_dependencies(msan clang_rt.msan-${arch}-symbols
                           clang_rt.msan_cxx-${arch}-symbols)
   endif()
 endforeach()
 
 add_compiler_rt_resource_file(msan_blacklist msan_blacklist.txt msan)
+list(APPEND MSAN_RUNTIME_LIBRARIES msan_blacklist)
 
 if(COMPILER_RT_INCLUDE_TESTS)
   add_subdirectory(tests)
 endif()

compiler-rt/lib/msan/msan_blacklist.txt

 # Blacklist for MemorySanitizer. Turns off instrumentation of particular
 # functions or sources. Use with care. You may set location of blacklist
 # at compile-time using -fsanitize-blacklist=<path> flag.
 
 # Example usage:
 # fun:*bad_function_name*
 # src:file_with_tricky_code.cc
+
+# https://bugs.llvm.org/show_bug.cgi?id=31877
+fun:__gxx_personality_*

compiler-rt/lib/msan/tests/CMakeLists.txt

 include(CheckCXXCompilerFlag)
 include(CompilerRTCompile)
 include(CompilerRTLink)
 
 include_directories(..)
 include_directories(../..)
 
 set(MSAN_LIBCXX_CFLAGS
   -fsanitize=memory
   -fsanitize-memory-track-origins
-  -Wno-pedantic)
+  -Wno-pedantic
+  -Xclang -fdepfile-entry=${COMPILER_RT_OUTPUT_DIR}/share/msan_blacklist.txt
+  )
 
 # Unittest sources and build flags.
 set(MSAN_UNITTEST_SOURCES
   msan_test.cpp
   msan_test_main.cpp
   )
 set(MSAN_LOADABLE_SOURCE
   msan_loadable.cpp
   )
 set(MSAN_UNITTEST_HEADERS
   msan_test_config.h
   ../../../include/sanitizer/msan_interface.h
   )
 set(MSAN_UNITTEST_COMMON_CFLAGS
   -nostdinc++
   -isystem ${COMPILER_RT_LIBCXX_PATH}/include
   ${COMPILER_RT_UNITTEST_CFLAGS}
   ${COMPILER_RT_GTEST_CFLAGS}
   -I${COMPILER_RT_SOURCE_DIR}/include
   -I${COMPILER_RT_SOURCE_DIR}/lib
   -I${COMPILER_RT_SOURCE_DIR}/lib/msan
   -g
   -O2
-  -fno-exceptions
   -fno-omit-frame-pointer
   -mno-omit-leaf-frame-pointer
   -Wno-deprecated-declarations
   -Wno-unused-variable
   -Wno-zero-length-array
   -Wno-uninitialized
   -Werror=sign-compare
   -Wno-gnu-zero-variadic-macro-arguments
macro(add_msan_tests_for_arch arch kind cflags)
   # Instrumented loadable library tests.
   set(MSAN_LOADABLE_SO)
   msan_link_shared(MSAN_LOADABLE_SO "libmsan_loadable" ${arch} "${kind}"
                    OBJECTS ${MSAN_INST_LOADABLE_OBJECTS}
                    DEPS ${MSAN_INST_LOADABLE_OBJECTS})
 
   set(MSAN_TEST_OBJECTS ${MSAN_INST_TEST_OBJECTS} ${MSAN_INST_GTEST})
   set(MSAN_TEST_DEPS ${MSAN_TEST_OBJECTS} libcxx_msan_${arch}-build
-                     ${MSAN_LOADABLE_SO})
+                     ${MSAN_LOADABLE_SO}
+         "${MSAN_LIBCXX_DIR}/libc++.a" "${MSAN_LIBCXX_DIR}/libc++abi.a")
   if(NOT COMPILER_RT_STANDALONE_BUILD)
     list(APPEND MSAN_TEST_DEPS msan)
   endif()
   get_target_flags_for_arch(${arch} TARGET_LINK_FLAGS)
   add_compiler_rt_test(MsanUnitTests "Msan-${arch}${kind}-Test" ${arch}
-    OBJECTS ${MSAN_TEST_OBJECTS} "${MSAN_LIBCXX_DIR}/libc++.a"
+    OBJECTS ${MSAN_TEST_OBJECTS} "${MSAN_LIBCXX_DIR}/libc++.a" "${MSAN_LIBCXX_DIR}/libc++abi.a"
     DEPS ${MSAN_TEST_DEPS}
     LINK_FLAGS ${MSAN_UNITTEST_LINK_FLAGS}
                ${TARGET_LINK_FLAGS})
 endmacro()
 
 # We should only build MSan unit tests if we can build instrumented libcxx.
 if(COMPILER_RT_CAN_EXECUTE_TESTS AND
    COMPILER_RT_LIBCXX_PATH AND

compiler-rt/lib/msan/tests/msan_test.cpp

TEST(MemorySanitizer, Bmi) {
   if (HaveBmi()) {
     TestBZHI();
     TestBEXTR();
     TestPDEP();
     TestPEXT();
   }
 }
 #endif // defined(__x86_64__)
+
+
+#include <sanitizer/msan_interface.h>
+
+namespace {
+volatile long z;
+
+__attribute__((noinline,optnone)) void f(long a, long b, long c, long d, long e, long f) {
+  z = a + b + c + d + e + f;
+}
+
+__attribute__((noinline,optnone)) void throw_stuff() {
+  throw 5;
+}
+
+TEST(MemorySanitizer, throw_catch) {
+  long x;
+  // Poison __msan_param_tls.
+  __msan_poison(&x, sizeof(x));
+  f(x, x, x, x, x, x);
+  try {
+    // This calls __gxx_personality_v0 through some libgcc_s function.
+    // __gxx_personality_v0 is instrumented, libgcc_s is not; as a result,
+    // __msan_param_tls is not updated and __gxx_personality_v0 can find
+    // leftover poison from the previous call.
+    // A suppression in msan_blacklist.txt makes it work.
+    throw_stuff();
+  } catch (const int &e) {
+    // pass
+  }
+}
+} // namespace