diff --git a/compiler-rt/lib/msan/lit_tests/CMakeLists.txt b/compiler-rt/lib/msan/lit_tests/CMakeLists.txt
index 3fcb3480f284..38d1e59e709e 100644
--- a/compiler-rt/lib/msan/lit_tests/CMakeLists.txt
+++ b/compiler-rt/lib/msan/lit_tests/CMakeLists.txt
@@ -11,7 +11,7 @@ if(MSAN_CAN_INSTRUMENT_LIBCXX)
     ${CMAKE_CURRENT_BINARY_DIR}/Unit/lit.site.cfg)
 endif()
 
-if(COMPILER_RT_CAN_EXECUTE_TESTS)
+if(COMPILER_RT_CAN_EXECUTE_TESTS AND CAN_TARGET_x86_64)
   # Run MSan tests only if we're sure we may produce working binaries.
   set(MSAN_TEST_DEPS
     ${SANITIZER_COMMON_LIT_TEST_DEPS}
diff --git a/compiler-rt/lib/msan/lit_tests/lit.cfg b/compiler-rt/lib/msan/lit_tests/lit.cfg
index fd88ca04d42c..da1bde6dd04a 100644
--- a/compiler-rt/lib/msan/lit_tests/lit.cfg
+++ b/compiler-rt/lib/msan/lit_tests/lit.cfg
@@ -56,7 +56,8 @@ clang_msan_cflags = ["-fsanitize=memory",
                      "-mno-omit-leaf-frame-pointer",
                      "-fno-omit-frame-pointer",
                      "-fno-optimize-sibling-calls",
-                     "-g"]
+                     "-g",
+                     "-m64"]
 clang_msan_cxxflags = ["--driver-mode=g++ "] + clang_msan_cflags
 config.substitutions.append( ("%clang_msan ",
                               " ".join([config.clang] + clang_msan_cflags) + 
diff --git a/compiler-rt/lib/tsan/lit_tests/CMakeLists.txt b/compiler-rt/lib/tsan/lit_tests/CMakeLists.txt
index 53e5015d1bc4..1f2fbf98e080 100644
--- a/compiler-rt/lib/tsan/lit_tests/CMakeLists.txt
+++ b/compiler-rt/lib/tsan/lit_tests/CMakeLists.txt
@@ -8,7 +8,7 @@ configure_lit_site_cfg(
   ${CMAKE_CURRENT_BINARY_DIR}/Unit/lit.site.cfg
   )
 
-if(COMPILER_RT_CAN_EXECUTE_TESTS)
+if(COMPILER_RT_CAN_EXECUTE_TESTS AND CAN_TARGET_x86_64)
   # Run TSan output tests only if we're sure we can produce working binaries.
   set(TSAN_TEST_DEPS
     ${SANITIZER_COMMON_LIT_TEST_DEPS}
@@ -25,7 +25,7 @@ if(COMPILER_RT_CAN_EXECUTE_TESTS)
     DEPENDS ${TSAN_TEST_DEPS}
     )
   set_target_properties(check-tsan PROPERTIES FOLDER "TSan unittests")
-elseif(LLVM_INCLUDE_TESTS)
+elseif(LLVM_INCLUDE_TESTS AND CAN_TARGET_x86_64)
   # Otherwise run only TSan unit tests (they are linked using the
   # host compiler).
   add_lit_testsuite(check-tsan "Running ThreadSanitizer tests"
diff --git a/compiler-rt/lib/tsan/lit_tests/lit.cfg b/compiler-rt/lib/tsan/lit_tests/lit.cfg
index 0cdb4d838941..c4193639f493 100644
--- a/compiler-rt/lib/tsan/lit_tests/lit.cfg
+++ b/compiler-rt/lib/tsan/lit_tests/lit.cfg
@@ -62,7 +62,8 @@ clang_tsan_cflags = ("-fsanitize=thread "
                       + "-g "
                       + "-Wall "
                       + "-lpthread "
-                      + "-ldl ")
+                      + "-ldl "
+                      + "-m64 ")
 clang_tsan_cxxflags = "--driver-mode=g++ " + clang_tsan_cflags
 config.substitutions.append( ("%clangxx_tsan ", (" " + config.clang + " " +
                                                 clang_tsan_cxxflags + " ")) )