[CMake] Avoid accidental C++ standard library dependency in sanitizers

petrhosek · petrhosek · commit 287c318690f1 · 2020-10-14T18:26:56.000-07:00
While sanitizers don't use C++ standard library, we could still end up accidentally including or linking it just by the virtue of using the C++ compiler. Pass -nostdinc++ and -nostdlib++ to avoid these accidental dependencies. Differential Revision: https://reviews.llvm.org/D88922
diff --git a/compiler-rt/CMakeLists.txt b/compiler-rt/CMakeLists.txt
@@ -437,6 +437,13 @@ if("${CMAKE_SYSTEM_NAME}" STREQUAL "Fuchsia")
   list(APPEND SANITIZER_COMMON_LINK_LIBS zircon)
 endif()
 
+# We don't use the C++ standard library, so avoid including it by mistake.
+append_list_if(COMPILER_RT_HAS_NOSTDINCXX_FLAG -nostdinc++ SANITIZER_COMMON_CFLAGS)
+append_list_if(COMPILER_RT_HAS_NOSTDLIBXX_FLAG -nostdlib++ SANITIZER_COMMON_LINK_FLAGS)
+
+# Remove -stdlib= which is unused when passing -nostdinc++.
+string(REGEX REPLACE "-stdlib=[a-zA-Z+]*" "" CMAKE_CXX_FLAGS ${CMAKE_CXX_FLAGS})
+
 macro(append_libcxx_libs var)
   if (${var}_INTREE)
     if (SANITIZER_USE_STATIC_LLVM_UNWINDER AND (TARGET unwind_static OR HAVE_LIBUNWIND))
diff --git a/compiler-rt/cmake/Modules/CompilerRTUtils.cmake b/compiler-rt/cmake/Modules/CompilerRTUtils.cmake
@@ -80,6 +80,13 @@ function(list_replace input_list old new)
   set(${input_list} "${replaced_list}" PARENT_SCOPE)
 endfunction()
 
+macro(list_filter list element)
+  list(FIND ${list} ${element} index)
+  if(NOT index EQUAL -1)
+    list(REMOVE_AT ${list} ${index})
+  endif()
+endmacro()
+
 # Takes ${ARGN} and puts only supported architectures in @out_var list.
 function(filter_available_targets out_var)
   set(archs ${${out_var}})
diff --git a/compiler-rt/cmake/config-ix.cmake b/compiler-rt/cmake/config-ix.cmake
@@ -123,6 +123,7 @@ check_symbol_exists(__func__ "" COMPILER_RT_HAS_FUNC_SYMBOL)
 
 # Includes.
 check_cxx_compiler_flag(-nostdinc++ COMPILER_RT_HAS_NOSTDINCXX_FLAG)
+check_cxx_compiler_flag(-nostdlib++ COMPILER_RT_HAS_NOSTDLIBXX_FLAG)
 check_include_files("sys/auxv.h"    COMPILER_RT_HAS_AUXV)
 
 # Libraries.
diff --git a/compiler-rt/lib/asan/CMakeLists.txt b/compiler-rt/lib/asan/CMakeLists.txt
@@ -111,10 +111,6 @@ append_list_if(COMPILER_RT_HAS_LIBPTHREAD pthread ASAN_DYNAMIC_LIBS)
 append_list_if(COMPILER_RT_HAS_LIBLOG log ASAN_DYNAMIC_LIBS)
 append_list_if(MINGW "${MINGW_LIBRARIES}" ASAN_DYNAMIC_LIBS)
 
-if (TARGET cxx-headers OR HAVE_LIBCXX)
-  set(ASAN_DEPS cxx-headers)
-endif()
-
 # Compile ASan sources into an object library.
 
 add_compiler_rt_object_libraries(RTAsan_dynamic
@@ -123,39 +119,34 @@ add_compiler_rt_object_libraries(RTAsan_dynamic
   SOURCES ${ASAN_SOURCES} ${ASAN_CXX_SOURCES}
   ADDITIONAL_HEADERS ${ASAN_HEADERS}
   CFLAGS ${ASAN_DYNAMIC_CFLAGS}
-  DEFS ${ASAN_DYNAMIC_DEFINITIONS}
-  DEPS ${ASAN_DEPS})
+  DEFS ${ASAN_DYNAMIC_DEFINITIONS})
 
 if(NOT APPLE)
   add_compiler_rt_object_libraries(RTAsan
     ARCHS ${ASAN_SUPPORTED_ARCH}
     SOURCES ${ASAN_SOURCES}
     ADDITIONAL_HEADERS ${ASAN_HEADERS}
     CFLAGS ${ASAN_CFLAGS}
-    DEFS ${ASAN_COMMON_DEFINITIONS}
-    DEPS ${ASAN_DEPS})
+    DEFS ${ASAN_COMMON_DEFINITIONS})
   add_compiler_rt_object_libraries(RTAsan_cxx
     ARCHS ${ASAN_SUPPORTED_ARCH}
     SOURCES ${ASAN_CXX_SOURCES}
     ADDITIONAL_HEADERS ${ASAN_HEADERS}
     CFLAGS ${ASAN_CFLAGS}
-    DEFS ${ASAN_COMMON_DEFINITIONS}
-    DEPS ${ASAN_DEPS})
+    DEFS ${ASAN_COMMON_DEFINITIONS})
   add_compiler_rt_object_libraries(RTAsan_preinit
     ARCHS ${ASAN_SUPPORTED_ARCH}
     SOURCES ${ASAN_PREINIT_SOURCES}
     ADDITIONAL_HEADERS ${ASAN_HEADERS}
     CFLAGS ${ASAN_CFLAGS}
-    DEFS ${ASAN_COMMON_DEFINITIONS}
-    DEPS ${ASAN_DEPS})
+    DEFS ${ASAN_COMMON_DEFINITIONS})
 
   file(WRITE ${CMAKE_CURRENT_BINARY_DIR}/dummy.cpp "")
   add_compiler_rt_object_libraries(RTAsan_dynamic_version_script_dummy
     ARCHS ${ASAN_SUPPORTED_ARCH}
     SOURCES ${CMAKE_CURRENT_BINARY_DIR}/dummy.cpp
     CFLAGS ${ASAN_DYNAMIC_CFLAGS}
-    DEFS ${ASAN_DYNAMIC_DEFINITIONS}
-    DEPS ${ASAN_DEPS})
+    DEFS ${ASAN_DYNAMIC_DEFINITIONS})
 endif()
 
 # Build ASan runtimes shipped with Clang.
@@ -250,8 +241,7 @@ else()
         ARCHS ${arch}
         SOURCES asan_win_weak_interception.cpp
         CFLAGS ${ASAN_CFLAGS} -DSANITIZER_DYNAMIC
-        DEFS ${ASAN_COMMON_DEFINITIONS}
-        DEPS ${ASAN_DEPS})
+        DEFS ${ASAN_COMMON_DEFINITIONS})
       set(ASAN_DYNAMIC_WEAK_INTERCEPTION
           AsanWeakInterception
           UbsanWeakInterception
@@ -296,8 +286,7 @@ else()
         SOURCES asan_globals_win.cpp
                 asan_win_dll_thunk.cpp
         CFLAGS ${ASAN_CFLAGS} -DSANITIZER_DLL_THUNK
-        DEFS ${ASAN_COMMON_DEFINITIONS}
-        DEPS ${ASAN_DEPS})
+        DEFS ${ASAN_COMMON_DEFINITIONS})
 
       add_compiler_rt_runtime(clang_rt.asan_dll_thunk
         STATIC
@@ -322,8 +311,7 @@ else()
         SOURCES asan_globals_win.cpp
                 asan_win_dynamic_runtime_thunk.cpp
         CFLAGS ${ASAN_CFLAGS} ${DYNAMIC_RUNTIME_THUNK_CFLAGS}
-        DEFS ${ASAN_COMMON_DEFINITIONS}
-        DEPS ${ASAN_DEPS})
+        DEFS ${ASAN_COMMON_DEFINITIONS})
 
       add_compiler_rt_runtime(clang_rt.asan_dynamic_runtime_thunk
         STATIC
diff --git a/compiler-rt/lib/fuzzer/CMakeLists.txt b/compiler-rt/lib/fuzzer/CMakeLists.txt
@@ -60,11 +60,15 @@ set(LIBFUZZER_CFLAGS ${SANITIZER_COMMON_CFLAGS})
 if(OS_NAME MATCHES "Linux|Fuchsia" AND
    COMPILER_RT_LIBCXX_PATH AND
    COMPILER_RT_LIBCXXABI_PATH)
-  list(APPEND LIBFUZZER_CFLAGS -nostdinc++ -D_LIBCPP_ABI_VERSION=Fuzzer)
+  list(APPEND LIBFUZZER_CFLAGS -D_LIBCPP_ABI_VERSION=Fuzzer)
   # Remove -stdlib= which is unused when passing -nostdinc++.
   string(REGEX REPLACE "-stdlib=[a-zA-Z+]*" "" CMAKE_CXX_FLAGS ${CMAKE_CXX_FLAGS})
-elseif(TARGET cxx-headers OR HAVE_LIBCXX)
-  set(LIBFUZZER_DEPS cxx-headers)
+else()
+  # libFuzzer uses C++ standard library headers so drop -nostdinc++.
+  list_filter(LIBFUZZER_CFLAGS "-nostdinc++")
+  if(TARGET cxx-headers OR HAVE_LIBCXX)
+    set(LIBFUZZER_DEPS cxx-headers)
+  endif()
 endif()
 
 append_list_if(COMPILER_RT_HAS_OMIT_FRAME_POINTER_FLAG -fno-omit-frame-pointer LIBFUZZER_CFLAGS)
diff --git a/compiler-rt/lib/hwasan/CMakeLists.txt b/compiler-rt/lib/hwasan/CMakeLists.txt
@@ -71,10 +71,6 @@ append_list_if(COMPILER_RT_HAS_LIBRT rt HWASAN_DYNAMIC_LIBS)
 append_list_if(COMPILER_RT_HAS_LIBM m HWASAN_DYNAMIC_LIBS)
 append_list_if(COMPILER_RT_HAS_LIBPTHREAD pthread HWASAN_DYNAMIC_LIBS)
 
-if (TARGET cxx-headers OR HAVE_LIBCXX)
-  set(HWASAN_DEPS cxx-headers)
-endif()
-
 # Static runtime library.
 add_compiler_rt_component(hwasan)
 
@@ -83,30 +79,26 @@ add_compiler_rt_object_libraries(RTHwasan
   SOURCES ${HWASAN_RTL_SOURCES}
   ADDITIONAL_HEADERS ${HWASAN_RTL_HEADERS}
   CFLAGS ${HWASAN_RTL_CFLAGS}
-  DEFS ${HWASAN_DEFINITIONS}
-  DEPS ${HWASAN_DEPS})
+  DEFS ${HWASAN_DEFINITIONS})
 add_compiler_rt_object_libraries(RTHwasan_cxx
   ARCHS ${HWASAN_SUPPORTED_ARCH}
   SOURCES ${HWASAN_RTL_CXX_SOURCES}
   ADDITIONAL_HEADERS ${HWASAN_RTL_HEADERS}
   CFLAGS ${HWASAN_RTL_CFLAGS}
-  DEFS ${HWASAN_DEFINITIONS}
-  DEPS ${HWASAN_DEPS})
+  DEFS ${HWASAN_DEFINITIONS})
 add_compiler_rt_object_libraries(RTHwasan_dynamic
   ARCHS ${HWASAN_SUPPORTED_ARCH}
   SOURCES ${HWASAN_RTL_SOURCES} ${HWASAN_RTL_CXX_SOURCES}
   ADDITIONAL_HEADERS ${HWASAN_RTL_HEADERS}
   CFLAGS ${HWASAN_DYNAMIC_CFLAGS}
-  DEFS ${HWASAN_DEFINITIONS}
-  DEPS ${HWASAN_DEPS})
+  DEFS ${HWASAN_DEFINITIONS})
 
 file(WRITE ${CMAKE_CURRENT_BINARY_DIR}/dummy.cpp "")
 add_compiler_rt_object_libraries(RTHwasan_dynamic_version_script_dummy
   ARCHS ${HWASAN_SUPPORTED_ARCH}
   SOURCES ${CMAKE_CURRENT_BINARY_DIR}/dummy.cpp
   CFLAGS ${HWASAN_DYNAMIC_CFLAGS}
-  DEFS ${HWASAN_DEFINITIONS}
-  DEPS ${HWASAN_DEPS})
+  DEFS ${HWASAN_DEFINITIONS})
 
 foreach(arch ${HWASAN_SUPPORTED_ARCH})
   add_compiler_rt_runtime(clang_rt.hwasan
diff --git a/compiler-rt/lib/profile/CMakeLists.txt b/compiler-rt/lib/profile/CMakeLists.txt
@@ -113,8 +113,6 @@ endif()
 
 # We don't use the C++ Standard Library here, so avoid including it by mistake.
 append_list_if(COMPILER_RT_HAS_NOSTDINCXX_FLAG -nostdinc++ EXTRA_FLAGS)
-# Remove -stdlib= which is unused when passing -nostdinc++.
-string(REGEX REPLACE "-stdlib=[a-zA-Z+]*" "" CMAKE_CXX_FLAGS ${CMAKE_CXX_FLAGS})
 
 # This appears to be a C-only warning banning the use of locals in aggregate
 # initializers. All other compilers accept this, though.
diff --git a/compiler-rt/lib/xray/CMakeLists.txt b/compiler-rt/lib/xray/CMakeLists.txt
@@ -149,6 +149,8 @@ set(XRAY_COMMON_RUNTIME_OBJECT_LIBS
     RTSanitizerCommon
     RTSanitizerCommonLibc)
 
+# XRay uses C++ standard library headers so drop -nostdinc++.
+list_filter(XRAY_CFLAGS "-nostdinc++")
 if (TARGET cxx-headers OR HAVE_LIBCXX)
   set(XRAY_DEPS cxx-headers)
 endif()
