[CMake] Fix PR23539: Don't reference C++ ABI symbols prior to Mac OS 10.9.

[samsonov]

Summary

This patch implements step 1 from
https://llvm.org/bugs/show_bug.cgi?id=23539#c10

I'd appreciate if you could test it on Mac OS and verify that parts of UBSan
runtime that reference C++ ABI symbols are properly excluded, and fix ASan/UBSan
builds.

[hans]

Apologies for the delay. I tried this out on Mac, building like this:

$ cmake -GNinja -DCMAKE_BUILD_TYPE=Release -DCMAKE_C_FLAGS=-stdlib=libc++ -DCMAKE_CXX_FLAGS=-stdlib=libc++ -DCMAKE_OSX_DEPLOYMENT_TARGET=10.8 ..
$ ninja lib/clang/3.7.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib

The diff of that .dylib before and after your patch looks like this:

$ diff -u <(nm /tmp/before.dylib | sed 's/^[0-9a-f ]*//') <(nm /tmp/after.dylib | sed 's/^[0-9a-f ]*//')
--- /dev/fd/63	2015-06-24 15:54:26.000000000 -0700
+++ /dev/fd/62	2015-06-24 15:54:26.000000000 -0700
@@ -29,10 +29,8 @@
 __ZL15dump_once_guard
 __ZL15suppression_ctx
 t __ZL15unpoison_passwdPvPN11__sanitizer18__sanitizer_passwdE
-t __ZL16HandleCFIBadTypePN7__ubsan14CFIBadTypeDataEmNS_13ReportOptionsE
 __ZL16coverage_counter
 __ZL16coverage_enabled
-t __ZL16findBaseAtOffsetPKN10__cxxabiv117__class_type_infoEl
 t __ZL16handleNonNullArgPN7__ubsan14NonNullArgDataENS_13ReportOptionsE
 __ZL16ioctl_table_size
 t __ZL17StrtolFixAndCheckPvPKcPPcS2_i
@@ -147,7 +145,6 @@
 s __ZL20substitution_waitpid
 s __ZL20substitution_wordexp
 t __ZL21handleOutOfBoundsImplPN7__ubsan15OutOfBoundsDataEmNS_13ReportOptionsE
-t __ZL21isDerivedFromAtOffsetPKN10__cxxabiv117__class_type_infoES2_l
 s __ZL21substitution__longjmp
 s __ZL21substitution_asprintf
 s __ZL21substitution_endgrent
@@ -230,7 +227,6 @@
 t __ZL25handleVLABoundNotPositivePN7__ubsan12VLABoundDataEmNS_13ReportOptionsE
 s __ZL25substitution___cxa_atexit
 s __ZL25substitution_pthread_join
-t __ZL26HandleDynamicTypeCacheMissPN7__ubsan24DynamicTypeCacheMissDataEmmNS_13ReportOptionsE
 t __ZL26handleFunctionTypeMismatchPN7__ubsan24FunctionTypeMismatchDataEmNS_13ReportOptionsE
 t __ZL26handleShiftOutOfBoundsImplPN7__ubsan20ShiftOutOfBoundsDataEmmNS_13ReportOptionsE
 s __ZL26substitution_ether_hostton
@@ -1104,15 +1100,12 @@
 __ZN7__ubsan14TypeCheckKindsE
 t __ZN7__ubsan15InitializeFlagsEv
 t __ZN7__ubsan16InitAsStandaloneEv
-t __ZN7__ubsan16checkDynamicTypeEPvS0_m
 t __ZN7__ubsan18RegisterUbsanFlagsEPN11__sanitizer10FlagParserEPNS_5FlagsE
 t __ZN7__ubsan21IsVptrCheckSuppressedEPKc
 t __ZN7__ubsan21getSymbolizedLocationEm
 t __ZN7__ubsan22InitializeSuppressionsEv
 t __ZN7__ubsan27InitAsStandaloneIfNecessaryEv
 t __ZN7__ubsan28MaybeCallUbsanDefaultOptionsEv
-t __ZN7__ubsan28getDynamicTypeInfoFromObjectEPv
-t __ZN7__ubsan28getDynamicTypeInfoFromVtableEPv
 t __ZN7__ubsan4DiagD1Ev
 t __ZN7__ubsan4DiagD2Ev
 t __ZN7__ubsan4DiaglsERKNS_14TypeDescriptorE
@@ -1142,13 +1135,9 @@
 t __ZNK7__ubsan5Value12getUIntValueEv
 t __ZNK7__ubsan5Value13getFloatValueEv
 t __ZNK7__ubsan5Value19getPositiveIntValueEv
-U __ZTIN10__cxxabiv117__class_type_infoE
-U __ZTIN10__cxxabiv120__si_class_type_infoE
-U __ZTIN10__cxxabiv121__vmi_class_type_infoE
 __ZTIN11__sanitizer11FlagHandlerIPKcEE
 __ZTIN11__sanitizer11FlagHandlerIbEE
 __ZTIN11__sanitizer15FlagHandlerBaseE
-U __ZTISt9type_info
 s __ZTSN11__sanitizer11FlagHandlerIPKcEE
 s __ZTSN11__sanitizer11FlagHandlerIbEE
 s __ZTSN11__sanitizer15FlagHandlerBaseE
@@ -1172,9 +1161,7 @@
 s __ZTVN11__sanitizer2DDE
 s __ZTVN6__asan17AsanThreadContextE
 __ZZ23__asan_handle_no_returnE16reported_warning
-s __ZZL16HandleCFIBadTypePN7__ubsan14CFIBadTypeDataEmNS_13ReportOptionsEE14TypeCheckKinds
 __ZZL18MlockIsUnsupportedvE7printed
-__ZZL27getTypeCacheHashTableBucketmE21__ubsan_vptr_hash_set
 __ZZL28InitializeCommonInterceptorsvE12metadata_mem
 __ZZN11__sanitizer17GetPageSizeCachedEvE8PageSize
 __ZZN11__sanitizer9MmapOrDieEmPKcE15recursion_count
@@ -1339,7 +1326,6 @@
 t ___destroy_helper_block_20
 t ___destroy_helper_block_23
 t ___destroy_helper_block_26
-U ___dynamic_cast
 U ___error
 T ___lsan_disable
 T ___lsan_do_leak_check
@@ -1392,12 +1378,8 @@
 T ___ubsan_handle_add_overflow
 T ___ubsan_handle_add_overflow_abort
 T ___ubsan_handle_builtin_unreachable
-T ___ubsan_handle_cfi_bad_type
-T ___ubsan_handle_cfi_bad_type_abort
 T ___ubsan_handle_divrem_overflow
 T ___ubsan_handle_divrem_overflow_abort
-T ___ubsan_handle_dynamic_type_cache_miss
-T ___ubsan_handle_dynamic_type_cache_miss_abort
 T ___ubsan_handle_float_cast_overflow
 T ___ubsan_handle_float_cast_overflow_abort
 T ___ubsan_handle_function_type_mismatch
@@ -1423,7 +1405,6 @@
 T ___ubsan_handle_type_mismatch_abort
 T ___ubsan_handle_vla_bound_not_positive
 T ___ubsan_handle_vla_bound_not_positive_abort
-S ___ubsan_vptr_type_cache
 t ___wrap_dispatch_after_block_invoke
 t ___wrap_dispatch_async_block_invoke
 t ___wrap_dispatch_group_async_block_invoke

From what I can tell, that looks reasonable. In particular, __ZTISt9type_info is gone, which was the symbol causing our original link error.

lgtm

CMakeLists.txt

set(DARWIN_iossim_LINKFLAGS
     -isysroot ${IOSSIM_SDK_DIR})
 
   if(OSX_SDK_DIR)
     list(APPEND DARWIN_osx_CFLAGS -isysroot ${OSX_SDK_DIR})
     list(APPEND DARWIN_osx_LINKFLAGS -isysroot ${OSX_SDK_DIR})
   endif()
 endif()
 
+if(APPLE AND SANITIZER_MIN_OSX_VERSION VERSION_LESS "10.9")
+  # Mac OS X prior to 10.9 had problems with exporting symbols from
+  # libc++/libc++abi.
+  set(SANITIZER_CAN_USE_CXXABI FALSE)
+else()
+  set(SANITIZER_CAN_USE_CXXABI TRUE)
+endif()
+pythonize_bool(SANITIZER_CAN_USE_CXXABI)
+
 add_subdirectory(include)
 
 set(COMPILER_RT_LIBCXX_PATH ${LLVM_MAIN_SRC_DIR}/projects/libcxx)
 if(EXISTS ${COMPILER_RT_LIBCXX_PATH}/)
   set(COMPILER_RT_HAS_LIBCXX_SOURCES TRUE)
 else()
   set(COMPILER_RT_HAS_LIBCXX_SOURCES FALSE)
 endif()
 
 add_subdirectory(lib)
 
 if(COMPILER_RT_INCLUDE_TESTS)
   add_subdirectory(unittests)
 endif()
 add_subdirectory(test)

lib/ubsan/CMakeLists.txt

 append_no_rtti_flag(UBSAN_CFLAGS)
 set(UBSAN_STANDALONE_CFLAGS ${SANITIZER_COMMON_CFLAGS})
 append_no_rtti_flag(UBSAN_STANDALONE_CFLAGS)
 set(UBSAN_CXXFLAGS ${SANITIZER_COMMON_CFLAGS})
 
 add_custom_target(ubsan)
 
 if(APPLE)
+  set(UBSAN_COMMON_SOURCES ${UBSAN_SOURCES})
+  if(SANITIZER_CAN_USE_CXXABI)
+    list(APPEND UBSAN_COMMON_SOURCES ${UBSAN_CXX_SOURCES})
+  endif()
+
   # Common parts of UBSan runtime.
   add_compiler_rt_object_libraries(RTUbsan
     OS ${SANITIZER_COMMON_SUPPORTED_OS}
     ARCHS ${UBSAN_COMMON_SUPPORTED_ARCH}
-    SOURCES ${UBSAN_SOURCES} ${UBSAN_CXX_SOURCES}
+    SOURCES ${UBSAN_COMMON_SOURCES}
     CFLAGS ${UBSAN_CXXFLAGS})
 
   if(COMPILER_RT_HAS_UBSAN)
     # Initializer of standalone UBSan runtime.
     add_compiler_rt_object_libraries(RTUbsan_standalone
       OS ${SANITIZER_COMMON_SUPPORTED_OS}
       ARCHS ${UBSAN_SUPPORTED_ARCH}
       SOURCES ${UBSAN_STANDALONE_SOURCES}

test/lit.common.cfg

 if compiler_rt_arch:
   for arch in compiler_rt_arch.split(";"):
     config.available_features.add(arch + "-supported-target")
 
 compiler_rt_debug = getattr(config, 'compiler_rt_debug', False)
 if not compiler_rt_debug:
   config.available_features.add('compiler-rt-optimized')
 
+sanitizer_can_use_cxxabi = getattr(config, 'sanitizer_can_use_cxxabi', True)
+if sanitizer_can_use_cxxabi:
+  config.available_features.add('cxxabi')
+
 lit.util.usePlatformSdkOnDarwin(config, lit_config)
 
 def is_darwin_lto_supported():
   return os.path.exists(os.path.join(config.llvm_shlib_dir, 'libLTO.dylib'))
 
 def is_linux_lto_supported():
   if not os.path.exists(os.path.join(config.llvm_shlib_dir, 'LLVMgold.so')):
     return False

test/lit.common.configured.in

 set_default("gold_executable", "@GOLD_EXECUTABLE@")
 set_default("clang", "@COMPILER_RT_TEST_COMPILER@")
 set_default("compiler_id", "@COMPILER_RT_TEST_COMPILER_ID@")
 set_default("compiler_rt_arch", "@COMPILER_RT_SUPPORTED_ARCH@")
 set_default("python_executable", "@PYTHON_EXECUTABLE@")
 set_default("compiler_rt_debug", @COMPILER_RT_DEBUG_PYBOOL@)
 set_default("compiler_rt_libdir", "@COMPILER_RT_LIBRARY_OUTPUT_DIR@")
 set_default("emulator", "@COMPILER_RT_EMULATOR@")
+set_default("sanitizer_can_use_cxxabi", @SANITIZER_CAN_USE_CXXABI_PYBOOL@)
 
 # LLVM tools dir can be passed in lit parameters, so try to
 # apply substitution.
 try:
   config.llvm_tools_dir = config.llvm_tools_dir % lit_config.params
 except KeyError as e:
   key, = e.args
   lit_config.fatal("unable to find %r parameter, use '--param=%s=VALUE'" % (key, key))
 
 # Setup attributes common for all compiler-rt projects.
 lit_config.load_config(config, "@COMPILER_RT_SOURCE_DIR@/test/lit.common.cfg")

test/ubsan/TestCases/TypeCheck/vptr-virtual-base.cpp

 // RUN: %clangxx -frtti -fsanitize=vptr -fno-sanitize-recover=vptr -g %s -O3 -o %t
 // RUN: not %run %t 2>&1 | FileCheck %s
 
+// REQUIRES: cxxabi
+
 struct S { virtual int f() { return 0; } };
 struct T : virtual S {};
 
 struct Foo { virtual int f() { return 0; } };
 
 int main(int argc, char **argv) {
   Foo foo;
   T *t = (T*)&foo;
   S *s = t;
   // CHECK: vptr-virtual-base.cpp:[[@LINE-1]]:10: runtime error: cast to virtual base of address [[PTR:0x[0-9a-f]*]] which does not point to an object of type 'T'
   // CHECK-NEXT: [[PTR]]: note: object is of type 'Foo'
   return s->f();
 }

test/ubsan/TestCases/TypeCheck/vptr.cpp

 // RUN: UBSAN_OPTIONS="suppressions='%t.supp'" %run %t mV
 // RUN: UBSAN_OPTIONS="suppressions='%t.supp'" %run %t fV
 // RUN: UBSAN_OPTIONS="suppressions='%t.supp'" %run %t cV
 // RUN: UBSAN_OPTIONS="suppressions='%t.supp'" %run %t oU
 
 // RUN: echo "vptr_check:S" > %t.loc-supp
 // RUN: UBSAN_OPTIONS="suppressions='%t.loc-supp'" not %run %t x- 2>&1 | FileCheck %s --check-prefix=CHECK-LOC-SUPPRESS
 
-// REQUIRES: stable-runtime
+// REQUIRES: stable-runtime, cxxabi
 #include <new>
 #include <assert.h>
 #include <stdio.h>
 
 struct S {
   S() : a(0) {}
   ~S() {}
   int a;