Index: libcxxabi/src/CMakeLists.txt
===================================================================
--- libcxxabi/src/CMakeLists.txt
+++ libcxxabi/src/CMakeLists.txt
@@ -190,7 +190,11 @@
   set(cxxabi_static_sources $<TARGET_OBJECTS:cxxabi_objects>)
   if (LIBCXXABI_USE_LLVM_UNWINDER AND LIBCXXABI_STATICALLY_LINK_UNWINDER_IN_STATIC_LIBRARY)
     if (TARGET unwind_static OR HAVE_LIBUNWIND)
-      list(APPEND cxxabi_static_sources $<TARGET_OBJECTS:unwind_objects>)
+      if(LIBUNWIND_HERMETIC_STATIC_LIBRARY)
+        list(APPEND cxxabi_static_sources $<TARGET_OBJECTS:unwind_static_objects>)
+      else()
+        list(APPEND cxxabi_static_sources $<TARGET_OBJECTS:unwind_objects>)
+      endif()
     endif()
   endif()
   add_library(cxxabi_static STATIC ${cxxabi_static_sources})
Index: libunwind/CMakeLists.txt
===================================================================
--- libunwind/CMakeLists.txt
+++ libunwind/CMakeLists.txt
@@ -168,6 +168,9 @@
   message(FATAL_ERROR "LIBUNWIND_BUILD_32_BITS=ON is not supported on this platform.")
 endif()
 
+option(LIBUNWIND_HERMETIC_STATIC_LIBRARY
+  "Do not export any symbols from the static library." OFF)
+
 #===============================================================================
 # Configure System
 #===============================================================================
Index: libunwind/src/CMakeLists.txt
===================================================================
--- libunwind/src/CMakeLists.txt
+++ libunwind/src/CMakeLists.txt
@@ -105,17 +105,46 @@
 set_property(SOURCE ${LIBUNWIND_C_SOURCES}
              APPEND_STRING PROPERTY COMPILE_FLAGS " ${LIBUNWIND_C_FLAGS}")
 
+macro(unwind_object_library name)
+  cmake_parse_arguments(ARGS "" "" "DEFINES;FLAGS" ${ARGN})
+
 # Add a object library that contains the compiled source files.
-add_library(unwind_objects OBJECT ${LIBUNWIND_SOURCES} ${LIBUNWIND_HEADERS})
+  add_library(${name} OBJECT ${LIBUNWIND_SOURCES} ${LIBUNWIND_HEADERS})
+
+  if(ARGS_DEFINES)
+    target_compile_definitions(${name} PRIVATE ${ARGS_DEFINES})
+  endif()
+
+  set_target_properties(${name}
+                        PROPERTIES
+                          COMPILE_FLAGS "${LIBUNWIND_COMPILE_FLAGS}"
+                          POSITION_INDEPENDENT_CODE ON)
 
-set_target_properties(unwind_objects
-                      PROPERTIES
-                        COMPILE_FLAGS "${LIBUNWIND_COMPILE_FLAGS}"
-                        POSITION_INDEPENDENT_CODE ON)
+  if(ARGS_FLAGS)
+    target_compile_options(${name} PRIVATE ${ARGS_FLAGS})
+  endif()
+endmacro()
+
+if(LIBUNWIND_HERMETIC_STATIC_LIBRARY)
+  append_flags_if_supported(UNWIND_STATIC_OBJECTS_FLAGS -fvisibility=hidden)
+  append_flags_if_supported(UNWIND_STATIC_OBJECTS_FLAGS -fvisibility-global-new-delete-hidden)
+  unwind_object_library(unwind_static_objects
+    DEFINES
+      _LIBUNWIND_DISABLE_VISIBILITY_ANNOTATIONS
+      _LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS
+    FLAGS ${UNWIND_STATIC_OBJECTS_FLAGS})
+  unwind_object_library(unwind_shared_objects)
+  set(unwind_static_sources $<TARGET_OBJECTS:unwind_static_objects>)
+  set(unwind_shared_sources $<TARGET_OBJECTS:unwind_shared_objects>)
+else()
+  unwind_object_library(unwind_objects)
+  set(unwind_static_sources $<TARGET_OBJECTS:unwind_objects>)
+  set(unwind_shared_sources $<TARGET_OBJECTS:unwind_objects>)
+endif()
 
 # Build the shared library.
 if (LIBUNWIND_ENABLE_SHARED)
-  add_library(unwind_shared SHARED $<TARGET_OBJECTS:unwind_objects>)
+  add_library(unwind_shared SHARED ${unwind_shared_sources})
   if(COMMAND llvm_setup_rpath)
     llvm_setup_rpath(unwind_shared)
   endif()
@@ -134,7 +163,7 @@
 
 # Build the static library.
 if (LIBUNWIND_ENABLE_STATIC)
-  add_library(unwind_static STATIC $<TARGET_OBJECTS:unwind_objects>)
+  add_library(unwind_static STATIC ${unwind_static_sources})
   target_link_libraries(unwind_static ${libraries})
   set_target_properties(unwind_static
                         PROPERTIES