[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/experimental/filesystem b/include/experimental/filesystem
index fa2face..fe6e40b 100644
--- a/include/experimental/filesystem
+++ b/include/experimental/filesystem
@@ -249,7 +249,7 @@
uintmax_t available;
};
-enum class _LIBCPP_TYPE_VIS file_type : signed char
+enum class _LIBCPP_ENUM_VIS file_type : signed char
{
none = 0,
not_found = -1,
@@ -263,7 +263,7 @@
unknown = 8
};
-enum class _LIBCPP_TYPE_VIS perms : unsigned
+enum class _LIBCPP_ENUM_VIS perms : unsigned
{
none = 0,
@@ -323,7 +323,7 @@
inline perms& operator^=(perms& _LHS, perms _RHS)
{ return _LHS = _LHS ^ _RHS; }
-enum class _LIBCPP_TYPE_VIS copy_options : unsigned short
+enum class _LIBCPP_ENUM_VIS copy_options : unsigned short
{
none = 0,
skip_existing = 1,
@@ -367,7 +367,7 @@
{ return _LHS = _LHS ^ _RHS; }
-enum class directory_options : unsigned char
+enum class _LIBCPP_ENUM_VIS directory_options : unsigned char
{
none = 0,
follow_directory_symlink = 1,
