do not export private symbols in wx shared libraries

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@58351 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/list.cpp

@@ -701,9 +701,13 @@ bool wxStringList::Member(const wxChar *s) const
 }
 
 #ifdef __WXWINCE__
-extern "C" int __cdecl
+extern "C"
+{
+static int __cdecl
 #else
-extern "C" int LINKAGEMODE
+extern "C"
+{
+static int LINKAGEMODE
 #endif
 
 wx_comparestrings(const void *arg1, const void *arg2)
@@ -714,6 +718,8 @@ wx_comparestrings(const void *arg1, const void *arg2)
   return wxStrcmp (*s1, *s2);
 }
 
+}   // end of extern "C" (required because of GCC Bug c++/33078
+
 // Sort a list of strings - deallocates old nodes, allocates new
 void wxStringList::Sort()
 {