[UBSan] Use shared library for UBSan on OS X (compiler-rt part).

[samsonov]

Summary

Switch to shared library for UBSan. Add support for building
UBSan on OSX and iossim by cargo-culting ASan build rules.

[kubamracek]

This doesn't build on my OS X 10.10 system, with the following link error (building with CMake+Ninja):

Linking CXX shared library lib/clang/3.7.0/lib/darwin/libclang_rt.ubsan_osx_dynamic.dylib
FAILED: ... /usr/bin/c++ -o lib/clang/3.7.0/lib/darwin/libclang_rt.ubsan_osx_dynamic.dylib ...
Undefined symbols for architecture x86_64:
  "typeinfo for __cxxabiv1::__class_type_info", referenced from:
      __ubsan::checkDynamicType(void*, void*, unsigned long) in ubsan_type_hash.cc.o
      isDerivedFromAtOffset(__cxxabiv1::__class_type_info const*, __cxxabiv1::__class_type_info const*, long) in ubsan_type_hash.cc.o
      findBaseAtOffset(__cxxabiv1::__class_type_info const*, long) in ubsan_type_hash.cc.o
  "typeinfo for __cxxabiv1::__si_class_type_info", referenced from:
      isDerivedFromAtOffset(__cxxabiv1::__class_type_info const*, __cxxabiv1::__class_type_info const*, long) in ubsan_type_hash.cc.o
      findBaseAtOffset(__cxxabiv1::__class_type_info const*, long) in ubsan_type_hash.cc.o
  "typeinfo for __cxxabiv1::__vmi_class_type_info", referenced from:
      isDerivedFromAtOffset(__cxxabiv1::__class_type_info const*, __cxxabiv1::__class_type_info const*, long) in ubsan_type_hash.cc.o
      findBaseAtOffset(__cxxabiv1::__class_type_info const*, long) in ubsan_type_hash.cc.o
ld: symbol(s) not found for architecture x86_64

This looks like the same issue that was discussed at http://reviews.llvm.org/D6960, and the proposed solution (explicitly linking against libc++abi.dylib) should fix this. I'm not sure if that's the right thing to do here, it was suggested that we shouldn't link against libc++abi, and the issue should be fixed in libc++ re-export list. However, this would only be available in the next OS X version. So unless someone has a strong reason why not, we might need to really explicitly link against libc++abi.

[samsonov]

I think we should just link against libc++abi to make it work in the current Mac OS version. Can you check if linking ubsan dylib with -lc++abi would fix the issue?

[kubamracek]

In D8473#144733, @samsonov wrote:

I think we should just link against libc++abi to make it work in the current Mac OS version. Can you check if linking ubsan dylib with -lc++abi would fix the issue?

Yes, it does fix the issue.

[samsonov]

OK, I will make this changes and try to submit the patch on Monday.

[zaks.anna]

I was able to build the makefile build with these changes.

make/platform/clang_darwin.mk

242

I think we should pass -lc++ on all platforms to make sure we link against libc++.

[samsonov]

make/platform/clang_darwin.mk

242

Why do we then explicitly pass -stdlib=libc++ compile flags only on OS X, but not on iOS simulator? Could you somehow check if passing -stdlib=libc++ / -lc++ everywhere works?

[samsonov]

Thanks for testing this!

I've submitted this change in r233036. Let's see if it would work and not break the bots. Switching to libc++ everywhere (including in ASan) is a different thing, and we can proceed with it once we know how to test/verify it.

lib/ubsan/CMakeLists.txt

 
 set(UBSAN_CFLAGS ${SANITIZER_COMMON_CFLAGS})
 append_no_rtti_flag(UBSAN_CFLAGS)
 set(UBSAN_CXXFLAGS ${SANITIZER_COMMON_CFLAGS})
 
 add_custom_target(ubsan)
 
 if(APPLE)
-  # Build universal binary on APPLE.
-  add_compiler_rt_osx_static_runtime(clang_rt.ubsan_osx
+  foreach(os ${SANITIZER_COMMON_SUPPORTED_DARWIN_OS})
+    add_compiler_rt_darwin_object_library(RTUbsan ${os}
       ARCH ${UBSAN_SUPPORTED_ARCH}
       SOURCES ${UBSAN_SOURCES} ${UBSAN_CXX_SOURCES}
-            $<TARGET_OBJECTS:RTSanitizerCommon.osx>
       CFLAGS ${UBSAN_CXXFLAGS})
-  add_dependencies(ubsan clang_rt.ubsan_osx)
+
+    add_compiler_rt_darwin_dynamic_runtime(clang_rt.ubsan_${os}_dynamic ${os}
+      ARCH ${UBSAN_SUPPORTED_ARCH}
+      SOURCES $<TARGET_OBJECTS:RTUbsan.${os}>
+              $<TARGET_OBJECTS:RTSanitizerCommon.${os}>)
+
+    add_dependencies(ubsan clang_rt.ubsan_${os}_dynamic)
+  endforeach()
 else()
   # Build separate libraries for each target.
   foreach(arch ${UBSAN_SUPPORTED_ARCH})
     # Main UBSan runtime.
     add_compiler_rt_runtime(clang_rt.ubsan-${arch} ${arch} STATIC
       SOURCES ${UBSAN_SOURCES}
       CFLAGS ${UBSAN_CFLAGS})
     # C++-specific parts of UBSan runtime. Requires a C++ ABI library.

make/platform/clang_darwin.mk

 
 # Configurations which define the ASAN support functions.
 Configs += asan_osx_dynamic
 UniversalArchs.asan_osx_dynamic := $(call CheckArches,i386 x86_64 x86_64h,asan_osx_dynamic,$(OSX_SDK))
 
 Configs += asan_iossim_dynamic
 UniversalArchs.asan_iossim_dynamic := $(call CheckArches,i386 x86_64,asan_iossim_dynamic,$(IOSSIM_SDK))
 
-Configs += ubsan_osx
-UniversalArchs.ubsan_osx := $(call CheckArches,i386 x86_64 x86_64h,ubsan_osx,$(OSX_SDK))
+Configs += ubsan_osx_dynamic
+UniversalArchs.ubsan_osx_dynamic := $(call CheckArches,i386 x86_64 x86_64h,ubsan_osx_dynamic,$(OSX_SDK))
+
+Configs += ubsan_iossim_dynamic
+UniversalArchs.ubsan_iossim_dynamic := $(call CheckArches,i386 x86_64,ubsan_iossim_dynamic,$(IOSSIM_SDK))
 
 # Darwin 10.6 has a bug in cctools that makes it unable to use ranlib on our ARM
 # object files. If we are on that platform, strip out all ARM archs. We still
 # build the libraries themselves so that Clang can find them where it expects
 # them, even though they might not have an expected slice.
 ifneq ($(shell test -x /usr/bin/sw_vers && sw_vers -productVersion | grep 10.6),)
 UniversalArchs.ios := $(filter-out armv7, $(UniversalArchs.ios))
 UniversalArchs.cc_kext := $(filter-out armv7, $(UniversalArchs.cc_kext))

 OSX_DEPLOYMENT_ARGS += -isysroot $(OSX_SDK)
 IOS_DEPLOYMENT_ARGS += -isysroot $(IOS_SDK)
 IOS6_DEPLOYMENT_ARGS += -isysroot $(IOS_SDK)
 IOSSIM_DEPLOYMENT_ARGS += -isysroot $(IOSSIM_SDK)
 
 CFLAGS.eprintf    := $(CFLAGS) $(OSX_DEPLOYMENT_ARGS)
 CFLAGS.10.4   := $(CFLAGS) $(OSX_DEPLOYMENT_ARGS)
 
+SANITIZER_MACOSX_DEPLOYMENT_ARGS := -mmacosx-version-min=10.7
+SANITIZER_IOSSIM_DEPLOYMENT_ARGS := -mios-simulator-version-min=7.0 \
+  -isysroot $(IOSSIM_SDK)
+SANITIZER_CFLAGS := -fno-builtin -gline-tables-only
+
 CFLAGS.asan_osx_dynamic := \
-  $(CFLAGS) -mmacosx-version-min=10.7 \
+  $(CFLAGS) $(SANITIZER_MACOSX_DEPLOYMENT_ARGS) \
+  $(SANITIZER_CFLAGS) \
   -stdlib=libc++ \
-  -fno-builtin \
-  -gline-tables-only \
   -DMAC_INTERPOSE_FUNCTIONS=1 \
   -DASAN_DYNAMIC=1
 
 CFLAGS.asan_iossim_dynamic := \
-  $(CFLAGS) -mios-simulator-version-min=7.0 \
-        -isysroot $(IOSSIM_SDK) \
-        -fno-builtin \
-  -gline-tables-only \
+  $(CFLAGS) $(SANITIZER_IOSSIM_DEPLOYMENT_ARGS) \
+  $(SANITIZER_CFLAGS) \
   -DMAC_INTERPOSE_FUNCTIONS=1 \
   -DASAN_DYNAMIC=1
 
-CFLAGS.ubsan_osx := $(CFLAGS) -mmacosx-version-min=10.6 \
-  -fno-builtin
+CFLAGS.ubsan_osx_dynamic := \
+  $(CFLAGS) $(SANITIZER_MACOSX_DEPLOYMENT_ARGS) \
+  $(SANITIZER_CFLAGS) \
+  -stdlib=libc++
+
+CFLAGS.ubsan_iossim_dynamic := \
+  $(CFLAGS) $(SANITIZER_IOSSIM_DEPLOYMENT_ARGS) \
+  $(SANITIZER_CFLAGS)
+
 
 CFLAGS.ios.i386   := $(CFLAGS) $(IOSSIM_DEPLOYMENT_ARGS)
 CFLAGS.ios.x86_64 := $(CFLAGS) $(IOSSIM_DEPLOYMENT_ARGS)
 CFLAGS.ios.armv7  := $(CFLAGS) $(IOS_DEPLOYMENT_ARGS)
 CFLAGS.ios.armv7k := $(CFLAGS) $(IOS_DEPLOYMENT_ARGS)
 CFLAGS.ios.armv7s := $(CFLAGS) $(IOS_DEPLOYMENT_ARGS)
 CFLAGS.ios.arm64  := $(CFLAGS) $(IOS6_DEPLOYMENT_ARGS)
 CFLAGS.osx.i386   := $(CFLAGS) $(OSX_DEPLOYMENT_ARGS)

 CFLAGS.profile_osx.x86_64h := $(CFLAGS) $(OSX_DEPLOYMENT_ARGS)
 CFLAGS.profile_ios.i386    := $(CFLAGS) $(IOSSIM_DEPLOYMENT_ARGS)
 CFLAGS.profile_ios.x86_64  := $(CFLAGS) $(IOSSIM_DEPLOYMENT_ARGS)
 CFLAGS.profile_ios.armv7  := $(CFLAGS) $(IOS_DEPLOYMENT_ARGS)
 CFLAGS.profile_ios.armv7k := $(CFLAGS) $(IOS_DEPLOYMENT_ARGS)
 CFLAGS.profile_ios.armv7s := $(CFLAGS) $(IOS_DEPLOYMENT_ARGS)
 CFLAGS.profile_ios.arm64  := $(CFLAGS) $(IOS6_DEPLOYMENT_ARGS)
 
-# Configure the asan_osx_dynamic library to be built shared.
+SANITIZER_LDFLAGS := -undefined dynamic_lookup
+
 SHARED_LIBRARY.asan_osx_dynamic := 1
-LDFLAGS.asan_osx_dynamic := -lc++ -undefined dynamic_lookup -install_name @rpath/libclang_rt.asan_osx_dynamic.dylib \
-  -mmacosx-version-min=10.7
+LDFLAGS.asan_osx_dynamic := -lc++ $(SANITIZER_LDFLAGS) -install_name @rpath/libclang_rt.asan_osx_dynamic.dylib \
+  $(SANITIZER_MACOSX_DEPLOYMENT_ARGS)
 
-# Configure the asan_iossim_dynamic library to be built shared.
 SHARED_LIBRARY.asan_iossim_dynamic := 1
-# configure+make uses Clang, so we're using isysroot instead of --sysroot
-# or -Wl,-syslibroot.
-LDFLAGS.asan_iossim_dynamic := -undefined dynamic_lookup -install_name @rpath/libclang_rt.asan_iossim_dynamic.dylib \
-  -Wl,-ios_simulator_version_min,7.0.0 \
-  -mios-simulator-version-min=7.0 -isysroot $(IOSSIM_SDK)
+LDFLAGS.asan_iossim_dynamic := $(SANITIZER_LDFLAGS) -install_name @rpath/libclang_rt.asan_iossim_dynamic.dylib \
+  -Wl,-ios_simulator_version_min,7.0.0 $(SANITIZER_IOSSIM_DEPLOYMENT_ARGS)
+
+SHARED_LIBRARY.ubsan_osx_dynamic := 1
+LDFLAGS.ubsan_osx_dynamic := -lc++ $(SANITIZER_LDFLAGS) -install_name @rpath/libclang_rt.ubsan_osx_dynamic.dylib \
+  $(SANITIZER_MACOSX_DEPLOYMENT_ARGS)
+
+SHARED_LIBRARY.ubsan_iossim_dynamic := 1
+LDFLAGS.ubsan_iossim_dynamic := $(SANITIZER_LDFLAGS) -install_name @rpath/libclang_rt.ubsan_iossim_dynamic.dylib \
+  -Wl,-ios_simulator_version_min,7.0.0 $(SANITIZER_IOSSIM_DEPLOYMENT_ARGS)
 
 ifneq ($(OSX_SDK),)
 CFLAGS.asan_osx_dynamic += -isysroot $(OSX_SDK)
 LDFLAGS.asan_osx_dynamic += -isysroot $(OSX_SDK)
-CFLAGS.ubsan_osx += -isysroot $(OSX_SDK)
-LDFLAGS.ubsan_osx += -isysroot $(OSX_SDK)
+CFLAGS.ubsan_osx_dynamic += -isysroot $(OSX_SDK)
+LDFLAGS.ubsan_osx_dynamic += -isysroot $(OSX_SDK)
 endif
 
 FUNCTIONS.eprintf := eprintf
 FUNCTIONS.10.4 := eprintf floatundidf floatundisf floatundixf
 
 FUNCTIONS.ios     := divmodsi4 udivmodsi4 mulosi4 mulodi4 muloti4
 # On x86, the divmod functions reference divsi.
 FUNCTIONS.ios.i386    := $(FUNCTIONS.ios) \
                          divsi3 udivsi3
 FUNCTIONS.ios.x86_64  := $(FUNCTIONS.ios.i386)
 FUNCTIONS.ios.arm64   := mulsc3 muldc3 divsc3 divdc3
 
 FUNCTIONS.osx := mulosi4 mulodi4 muloti4
 
 FUNCTIONS.profile_osx := GCDAProfiling InstrProfiling InstrProfilingBuffer \
                          InstrProfilingFile InstrProfilingPlatformDarwin \
                          InstrProfilingRuntime
 FUNCTIONS.profile_ios := $(FUNCTIONS.profile_osx)
 
 FUNCTIONS.asan_osx_dynamic := $(AsanFunctions) $(AsanCXXFunctions) \
                               $(InterceptionFunctions) \
                               $(SanitizerCommonFunctions) \
-                        $(AsanDynamicFunctions)
+                              $(AsanDynamicFunctions)
 
 FUNCTIONS.asan_iossim_dynamic := $(AsanFunctions) $(AsanCXXFunctions) \
                                  $(InterceptionFunctions) \
                                  $(SanitizerCommonFunctions) \
-                           $(AsanDynamicFunctions)
+                                 $(AsanDynamicFunctions)
 
-FUNCTIONS.ubsan_osx := $(UbsanFunctions) $(UbsanCXXFunctions) \
+FUNCTIONS.ubsan_osx_dynamic := $(UbsanFunctions) $(UbsanCXXFunctions) \
+                               $(SanitizerCommonFunctions)
+
+FUNCTIONS.ubsan_iossim_dynamic := $(UbsanFunctions) $(UbsanCXXFunctions) \
                                   $(SanitizerCommonFunctions)
 
 CCKEXT_PROFILE_FUNCTIONS := \
   InstrProfiling \
   InstrProfilingBuffer \
   InstrProfilingPlatformDarwin
 
 CCKEXT_COMMON_FUNCTIONS := \
   $(CCKEXT_PROFILE_FUNCTIONS) \