Use default visibility everywhere.

asio/include/asio/detail/pop_options.hpp

diff --git a/asio/include/asio/detail/pop_options.hpp b/asio/include/asio/detail/pop_options.hpp
index 770302e..a41c1a0 100644
--- a/asio/include/asio/detail/pop_options.hpp
+++ b/asio/include/asio/detail/pop_options.hpp
@@ -23,6 +23,28 @@
 
 // Intel C++
 
+# if (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
+#  pragma GCC visibility pop
+# endif // (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
+
+#elif defined(__clang__)
+
+// Clang
+
+# if defined(__OBJC__)
+#  if !defined(__APPLE_CC__) || (__APPLE_CC__ <= 1)
+#   if defined(ASIO_OBJC_WORKAROUND)
+#    undef Protocol
+#    undef id
+#    undef ASIO_OBJC_WORKAROUND
+#   endif
+#  endif
+# endif
+
+# if !defined(_WIN32) && !defined(__WIN32__) && !defined(WIN32)
+#  pragma GCC visibility pop
+# endif // !defined(_WIN32) && !defined(__WIN32__) && !defined(WIN32)
+
 #elif defined(__GNUC__)
 
 // GNU C++
@@ -41,6 +63,10 @@
 #  endif
 # endif
 
+# if (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
+#  pragma GCC visibility pop
+# endif // (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
+
 #elif defined(__KCC)
 
 // Kai C++

asio/include/asio/detail/push_options.hpp

diff --git a/asio/include/asio/detail/push_options.hpp b/asio/include/asio/detail/push_options.hpp
index 62608ab..9c57044 100644
--- a/asio/include/asio/detail/push_options.hpp
+++ b/asio/include/asio/detail/push_options.hpp
@@ -23,6 +23,30 @@
 
 // Intel C++
 
+# if (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
+#  pragma GCC visibility push (default)
+# endif // (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
+
+#elif defined(__clang__)
+
+// Clang
+
+# if defined(__OBJC__)
+#  if !defined(__APPLE_CC__) || (__APPLE_CC__ <= 1)
+#   if !defined(ASIO_DISABLE_OBJC_WORKAROUND)
+#    if !defined(Protocol) && !defined(id)
+#     define Protocol cpp_Protocol
+#     define id cpp_id
+#     define ASIO_OBJC_WORKAROUND
+#    endif
+#   endif
+#  endif
+# endif
+
+# if !defined(_WIN32) && !defined(__WIN32__) && !defined(WIN32)
+#  pragma GCC visibility push (default)
+# endif // !defined(_WIN32) && !defined(__WIN32__) && !defined(WIN32)
+
 #elif defined(__GNUC__)
 
 // GNU C++
@@ -43,6 +67,10 @@
 #  endif
 # endif
 
+# if (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
+#  pragma GCC visibility push (default)
+# endif // (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
+
 #elif defined(__KCC)
 
 // Kai C++

asio/include/asio/detail/service_registry.hpp

diff --git a/asio/include/asio/detail/service_registry.hpp b/asio/include/asio/detail/service_registry.hpp
index 7438765..1bf7233 100644
--- a/asio/include/asio/detail/service_registry.hpp
+++ b/asio/include/asio/detail/service_registry.hpp
@@ -29,21 +29,9 @@
 
 namespace detail {
 
-#if defined(__GNUC__)
-# if (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
-#  pragma GCC visibility push (default)
-# endif // (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
-#endif // defined(__GNUC__)
-
 template <typename T>
 class typeid_wrapper {};
 
-#if defined(__GNUC__)
-# if (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
-#  pragma GCC visibility pop
-# endif // (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
-#endif // defined(__GNUC__)
-
 class service_registry
   : private noncopyable
 {