Index: test/cfi/lit.cfg
===================================================================
--- test/cfi/lit.cfg
+++ test/cfi/lit.cfg
@@ -5,13 +5,13 @@
 config.suffixes = ['.c', '.cpp', '.test']
 config.test_source_root = os.path.dirname(__file__)
 
-clang = ' '.join([config.compile_wrapper, config.clang, config.target_cflags])
-clangxx = ' '.join([config.compile_wrapper, config.clang, config.target_cflags] + config.cxx_mode_flags)
+clang = config.clang
+clangxx = config.clangxx
 
 config.substitutions.append((r"%clang ", clang + ' '))
 config.substitutions.append((r"%clangxx ", clangxx + ' '))
 if config.lto_supported:
-  clang_cfi = ' '.join(config.lto_launch + [clang] + config.lto_flags + ['-fsanitize=cfi '])
+  clang_cfi = clang + '-fsanitize=cfi '
 
   if config.cfi_lit_test_mode == "Devirt":
     config.available_features.add('devirt')
Index: test/cfi/lit.site.cfg.in
===================================================================
--- test/cfi/lit.site.cfg.in
+++ test/cfi/lit.site.cfg.in
@@ -5,6 +5,7 @@
 config.target_arch = "@CFI_TEST_TARGET_ARCH@"
 config.target_cflags = "@CFI_TEST_TARGET_CFLAGS@"
 config.use_lld = @CFI_TEST_USE_LLD@
+config.use_lto = True # CFI *requires* LTO.
 config.use_thinlto = @CFI_TEST_USE_THINLTO@
 
 lit_config.load_config(config, "@COMPILER_RT_BINARY_DIR@/test/lit.common.configured")
Index: test/lit.common.cfg
===================================================================
--- test/lit.common.cfg
+++ test/lit.common.cfg
@@ -321,3 +321,22 @@
 # because the test hangs or fails on one configuration and not the other.
 if config.android or (config.target_arch not in ['arm', 'armhf', 'aarch64']):
   config.available_features.add('stable-runtime')
+
+# Propagate the LLD/LTO into the clang config option, so nothing else is needed.
+run_wrapper = []
+target_cflags = [getattr(config, 'target_cflags', None)]
+extra_cflags = []
+
+if config.use_lto and config.lto_supported:
+  run_wrapper += config.lto_launch
+  extra_cflags += config.lto_flags
+elif config.use_lto and (not config.lto_supported):
+  config.unsupported = True
+
+if config.use_lld and config.has_lld and not config.use_lto:
+  extra_cflags += ["-fuse-ld=lld"]
+elif config.use_lld and (not config.has_lld):
+  config.unsupported = True
+
+config.clang = " " + " ".join(run_wrapper + [config.compile_wrapper, config.clang] + target_cflags + extra_cflags) + " "
+config.clangxx = " " + " ".join(run_wrapper + [config.compile_wrapper, config.clang] + target_cflags + config.cxx_mode_flags + extra_cflags) + " "
Index: test/lit.common.configured.in
===================================================================
--- test/lit.common.configured.in
+++ test/lit.common.configured.in
@@ -32,6 +32,7 @@
 set_default("can_symbolize", @CAN_SYMBOLIZE@)
 set_default("use_lld", False)
 set_default("use_thinlto", False)
+set_default("use_lto", config.use_thinlto)
 set_default("android", @ANDROID_PYBOOL@)
 config.available_features.add('target-is-%s' % config.target_arch)
 
Index: test/ubsan/CMakeLists.txt
===================================================================
--- test/ubsan/CMakeLists.txt
+++ test/ubsan/CMakeLists.txt
@@ -3,9 +3,20 @@
 set(UBSAN_TESTSUITES)
 set(UBSAN_TEST_DEPS ${SANITIZER_COMMON_LIT_TEST_DEPS})
 
-macro(add_ubsan_testsuite test_mode sanitizer arch)
+macro(add_ubsan_testsuite test_mode sanitizer arch lld thinlto)
   set(UBSAN_LIT_TEST_MODE "${test_mode}")
-  set(CONFIG_NAME ${UBSAN_LIT_TEST_MODE}-${arch})
+  set(CONFIG_NAME ${UBSAN_LIT_TEST_MODE})
+  if (${lld})
+    set(CONFIG_NAME ${CONFIG_NAME}-lld)
+    list(APPEND UBSAN_TEST_DEPS lld)
+  endif()
+  if (${thinlto})
+    set(CONFIG_NAME ${CONFIG_NAME}-thinlto)
+    list(APPEND UBSAN_TEST_DEPS LTO)
+  endif()
+  set(UBSAN_TEST_USE_LLD ${lld})
+  set(UBSAN_TEST_USE_THINLTO ${thinlto})
+  set(CONFIG_NAME ${CONFIG_NAME}-${arch})
   configure_lit_site_cfg(
     ${CMAKE_CURRENT_SOURCE_DIR}/lit.site.cfg.in
     ${CMAKE_CURRENT_BINARY_DIR}/${CONFIG_NAME}/lit.site.cfg)
@@ -15,6 +26,14 @@
   endif()
 endmacro()
 
+macro(add_ubsan_testsuites test_mode sanitizer arch)
+  add_ubsan_testsuite(${test_mode} ${sanitizer} ${arch} False False)
+
+  if(COMPILER_RT_HAS_LLD AND arch STREQUAL "x86_64" AND NOT (APPLE OR WIN32))
+    add_ubsan_testsuite(${test_mode} ${sanitizer} ${arch} True False)
+  endif()
+endmacro()
+
 set(UBSAN_TEST_ARCH ${UBSAN_SUPPORTED_ARCH})
 if(APPLE)
   darwin_filter_host_archs(UBSAN_SUPPORTED_ARCH UBSAN_TEST_ARCH)
@@ -23,20 +42,20 @@
 foreach(arch ${UBSAN_TEST_ARCH})
   set(UBSAN_TEST_TARGET_ARCH ${arch})
   get_test_cc_for_arch(${arch} UBSAN_TEST_TARGET_CC UBSAN_TEST_TARGET_CFLAGS)
-  add_ubsan_testsuite("Standalone" ubsan ${arch})
+  add_ubsan_testsuites("Standalone" ubsan ${arch})
 
   if(COMPILER_RT_HAS_ASAN AND ";${ASAN_SUPPORTED_ARCH};" MATCHES ";${arch};")
     # TODO(wwchrome): Re-enable ubsan for asan win 64-bit when ready.
     # Disable ubsan with AddressSanitizer tests for Windows 64-bit.
     if(NOT OS_NAME MATCHES "Windows" OR CMAKE_SIZEOF_VOID_P EQUAL 4)
-      add_ubsan_testsuite("AddressSanitizer" asan ${arch})
+      add_ubsan_testsuites("AddressSanitizer" asan ${arch})
     endif()
   endif()
   if(COMPILER_RT_HAS_MSAN AND ";${MSAN_SUPPORTED_ARCH};" MATCHES ";${arch};")
-    add_ubsan_testsuite("MemorySanitizer" msan ${arch})
+    add_ubsan_testsuites("MemorySanitizer" msan ${arch})
   endif()
   if(COMPILER_RT_HAS_TSAN AND ";${TSAN_SUPPORTED_ARCH};" MATCHES ";${arch};" AND NOT ANDROID)
-    add_ubsan_testsuite("ThreadSanitizer" tsan ${arch})
+    add_ubsan_testsuites("ThreadSanitizer" tsan ${arch})
   endif()
 endforeach()
 
@@ -45,7 +64,7 @@
     set(UBSAN_TEST_TARGET_ARCH ${arch})
     get_test_cc_for_arch(${arch} UBSAN_TEST_TARGET_CC UBSAN_TEST_TARGET_CFLAGS)
     set(UBSAN_TEST_TARGET_CFLAGS "${UBSAN_TEST_TARGET_CFLAGS} -lc++abi")
-    add_ubsan_testsuite("StandaloneStatic" ubsan ${arch})
+    add_ubsan_testsuites("StandaloneStatic" ubsan ${arch})
   endforeach()
 endif()
 
Index: test/ubsan/lit.common.cfg
===================================================================
--- test/ubsan/lit.common.cfg
+++ test/ubsan/lit.common.cfg
@@ -11,6 +11,9 @@
       "to lit.site.cfg " % attr_name)
   return attr_value
 
+# Setup config name.
+config.name = 'UBSan-' + config.name_suffix
+
 # Setup source root.
 config.test_source_root = os.path.dirname(__file__)
 
@@ -18,24 +21,19 @@
 # Choose between standalone and UBSan+ASan modes.
 ubsan_lit_test_mode = get_required_attr(config, 'ubsan_lit_test_mode')
 if ubsan_lit_test_mode == "Standalone":
-  config.name = 'UBSan-Standalone-' + config.target_arch
   config.available_features.add("ubsan-standalone")
   clang_ubsan_cflags = []
 elif ubsan_lit_test_mode == "StandaloneStatic":
-  config.name = 'UBSan-StandaloneStatic-' + config.target_arch
   config.available_features.add("ubsan-standalone-static")
   clang_ubsan_cflags = ['-static-libsan']
 elif ubsan_lit_test_mode == "AddressSanitizer":
-  config.name = 'UBSan-ASan-' + config.target_arch
   config.available_features.add("ubsan-asan")
   clang_ubsan_cflags = ["-fsanitize=address"]
   default_ubsan_opts += ['detect_leaks=0']
 elif ubsan_lit_test_mode == "MemorySanitizer":
-  config.name = 'UBSan-MSan-' + config.target_arch
   config.available_features.add("ubsan-msan")
   clang_ubsan_cflags = ["-fsanitize=memory"]
 elif ubsan_lit_test_mode == "ThreadSanitizer":
-  config.name = 'UBSan-TSan-' + config.target_arch
   config.available_features.add("ubsan-tsan")
   clang_ubsan_cflags = ["-fsanitize=thread"]
 else:
@@ -54,16 +52,11 @@
 config.substitutions.append(('%env_ubsan_opts=',
                              'env UBSAN_OPTIONS=' + default_ubsan_opts_str))
 
-def build_invocation(compile_flags):
-  return " " + " ".join([config.compile_wrapper, config.clang] + compile_flags) + " "
-
-target_cflags = [get_required_attr(config, "target_cflags")]
-clang_ubsan_cflags += target_cflags
-clang_ubsan_cxxflags = config.cxx_mode_flags + clang_ubsan_cflags
+clang_ubsan_cflags = " " + " ".join(clang_ubsan_cflags) + " "
 
 # Define %clang and %clangxx substitutions to use in test RUN lines.
-config.substitutions.append( ("%clang ", build_invocation(clang_ubsan_cflags)) )
-config.substitutions.append( ("%clangxx ", build_invocation(clang_ubsan_cxxflags)) )
+config.substitutions.append( ("%clang ", config.clang + clang_ubsan_cflags))
+config.substitutions.append( ("%clangxx ", config.clangxx + clang_ubsan_cflags))
 config.substitutions.append( ("%gmlt ", " ".join(config.debug_info_flags) + " ") )
 
 # Default test suffixes.
Index: test/ubsan/lit.site.cfg.in
===================================================================
--- test/ubsan/lit.site.cfg.in
+++ test/ubsan/lit.site.cfg.in
@@ -1,9 +1,12 @@
 @LIT_SITE_CFG_IN_HEADER@
 
 # Tool-specific config options.
+config.name_suffix = "@CONFIG_NAME@"
 config.ubsan_lit_test_mode = "@UBSAN_LIT_TEST_MODE@"
 config.target_cflags = "@UBSAN_TEST_TARGET_CFLAGS@"
 config.target_arch = "@UBSAN_TEST_TARGET_ARCH@"
+config.use_lld = @UBSAN_TEST_USE_LLD@
+config.use_thinlto = @UBSAN_TEST_USE_THINLTO@
 
 # Load common config for all compiler-rt lit tests.
 lit_config.load_config(config, "@COMPILER_RT_BINARY_DIR@/test/lit.common.configured")