[libc++] Fix and document visibility attributes for Clang, GCC and Windows.
Summary:
This patch fixes a number of problems with the visibility macros across GCC (on Unix) and Windows (DLL import/export semantics). All of the visibility macros are now documented under `DesignDocs/VisibilityMacros.rst`. Now I'll no longer forget the subtleties of each!
This patch adds two new visibility macros:
* `_LIBCPP_ENUM_VIS` for controlling the typeinfo of enum types. Only Clang supports this.
* `_LIBCPP_EXTERN_TEMPLATE_TYPE_VIS` for redefining visibility on explicit instantiation declarations. Clang and Windows require this.
After applying this patch GCC only emits one -Wattribute warning opposed to 30+.
Reviewers: mclow.lists, EricWF
Subscribers: beanz, mgorny, cfe-commits
Differential Revision: https://reviews.llvm.org/D24602
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@281673 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/vector b/include/vector
index cbe86a4..edcb7df 100644
--- a/include/vector
+++ b/include/vector
@@ -312,7 +312,7 @@
#pragma warning( push )
#pragma warning( disable: 4231 )
#endif // _LIBCPP_MSVC
-_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_TYPE_VIS __vector_base_common<true>)
+_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS __vector_base_common<true>)
#ifdef _LIBCPP_MSVC
#pragma warning( pop )
#endif // _LIBCPP_MSVC