[libc++] Implement exception_ptr on Windows

Summary:
This patch implements exception_ptr on Windows using the `__ExceptionPtrFoo` functions provided by MSVC.

The `__ExceptionPtrFoo` functions are defined inside the C++ standard library, `msvcprt`, which is unfortunate because it requires libc++ to link to the MSVC STL. However this doesn't seem to cause any immediate problems. However to be safe I kept all usages within the libc++ dylib so that user programs wouldn't have to link to MSVCPRT as well.

Note there are still 2 outstanding exception_ptr/nested_exception test failures.

* `current_exception.pass.cpp` needs to be rewritten for the Windows exception_ptr semantics which copy the exception every time.
* `rethrow_if_nested.pass.cpp` need investigation. It hits a stack overflow, likely from recursion.

This patch also gets most of the `<future>` tests passing as well.

Reviewers: mclow.lists, compnerd, bcraig, rmaprath, majnemer, BillyONeal, STL_MSFT

Subscribers: mgorny, cfe-commits

Differential Revision: https://reviews.llvm.org/D32927

llvm-svn: 302393

10 files changed, 17 insertions, 27 deletions

diff --git a/libcxx/test/std/language.support/support.exception/except.nested/assign.pass.cpp b/libcxx/test/std/language.support/support.exception/except.nested/assign.pass.cpp
index ec5575d072c..6338c8aaa26 100644
--- a/libcxx/test/std/language.support/support.exception/except.nested/assign.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/except.nested/assign.pass.cpp
@@ -7,9 +7,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-// exception_ptr has not been implemented on Windows
-// XFAIL: LIBCXX-WINDOWS-FIXME
-
 // <exception>
 
 // class nested_exception;
diff --git a/libcxx/test/std/language.support/support.exception/except.nested/ctor_copy.pass.cpp b/libcxx/test/std/language.support/support.exception/except.nested/ctor_copy.pass.cpp
index 92134c993af..4cbdbb2ec89 100644
--- a/libcxx/test/std/language.support/support.exception/except.nested/ctor_copy.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/except.nested/ctor_copy.pass.cpp
@@ -7,9 +7,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-// exception_ptr has not been implemented on Windows
-// XFAIL: LIBCXX-WINDOWS-FIXME
-
 // <exception>
 
 // class nested_exception;
diff --git a/libcxx/test/std/language.support/support.exception/except.nested/ctor_default.pass.cpp b/libcxx/test/std/language.support/support.exception/except.nested/ctor_default.pass.cpp
index 8f8503b254d..18ca9968ff5 100644
--- a/libcxx/test/std/language.support/support.exception/except.nested/ctor_default.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/except.nested/ctor_default.pass.cpp
@@ -7,9 +7,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-// exception_ptr has not been implemented on Windows
-// XFAIL: LIBCXX-WINDOWS-FIXME
-
 // <exception>
 
 // class nested_exception;
diff --git a/libcxx/test/std/language.support/support.exception/except.nested/rethrow_if_nested.pass.cpp b/libcxx/test/std/language.support/support.exception/except.nested/rethrow_if_nested.pass.cpp
index fe9cd6042ba..88e2253d08c 100644
--- a/libcxx/test/std/language.support/support.exception/except.nested/rethrow_if_nested.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/except.nested/rethrow_if_nested.pass.cpp
@@ -7,10 +7,11 @@
 //
 //===----------------------------------------------------------------------===//
 
-// exception_ptr has not been implemented on Windows
+// UNSUPPORTED: libcpp-no-exceptions
+
+// This test fails due to a stack overflow
 // XFAIL: LIBCXX-WINDOWS-FIXME
 
-// UNSUPPORTED: libcpp-no-exceptions
 // <exception>
 
 // class nested_exception;
diff --git a/libcxx/test/std/language.support/support.exception/except.nested/rethrow_nested.pass.cpp b/libcxx/test/std/language.support/support.exception/except.nested/rethrow_nested.pass.cpp
index 73d02da3933..d511a72f9f5 100644
--- a/libcxx/test/std/language.support/support.exception/except.nested/rethrow_nested.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/except.nested/rethrow_nested.pass.cpp
@@ -7,9 +7,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-// exception_ptr has not been implemented on Windows
-// XFAIL: LIBCXX-WINDOWS-FIXME
-
 // UNSUPPORTED: libcpp-no-exceptions
 // <exception>
 
diff --git a/libcxx/test/std/language.support/support.exception/except.nested/throw_with_nested.pass.cpp b/libcxx/test/std/language.support/support.exception/except.nested/throw_with_nested.pass.cpp
index 6353afcb239..6a9f25cd085 100644
--- a/libcxx/test/std/language.support/support.exception/except.nested/throw_with_nested.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/except.nested/throw_with_nested.pass.cpp
@@ -7,9 +7,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-// exception_ptr has not been implemented on Windows
-// XFAIL: LIBCXX-WINDOWS-FIXME
-
 // UNSUPPORTED: libcpp-no-exceptions
 // <exception>
 
diff --git a/libcxx/test/std/language.support/support.exception/propagation/current_exception.pass.cpp b/libcxx/test/std/language.support/support.exception/propagation/current_exception.pass.cpp
index 2046997774a..c33d64d06f0 100644
--- a/libcxx/test/std/language.support/support.exception/propagation/current_exception.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/propagation/current_exception.pass.cpp
@@ -7,7 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-// exception_ptr has not been implemented on Windows
+// This test needs to be rewritten for the Windows exception_ptr semantics
+// which copy the exception each time the exception_ptr is copied.
 // XFAIL: LIBCXX-WINDOWS-FIXME
 
 // UNSUPPORTED: libcpp-no-exceptions
diff --git a/libcxx/test/std/language.support/support.exception/propagation/exception_ptr.pass.cpp b/libcxx/test/std/language.support/support.exception/propagation/exception_ptr.pass.cpp
index 9621a736036..3aa8dcf55bb 100644
--- a/libcxx/test/std/language.support/support.exception/propagation/exception_ptr.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/propagation/exception_ptr.pass.cpp
@@ -7,9 +7,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-// exception_ptr has not been implemented on Windows
-// XFAIL: LIBCXX-WINDOWS-FIXME
-
 // <exception>
 
 // typedef unspecified exception_ptr;
diff --git a/libcxx/test/std/language.support/support.exception/propagation/make_exception_ptr.pass.cpp b/libcxx/test/std/language.support/support.exception/propagation/make_exception_ptr.pass.cpp
index 4980c656b2b..35821d9bd1b 100644
--- a/libcxx/test/std/language.support/support.exception/propagation/make_exception_ptr.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/propagation/make_exception_ptr.pass.cpp
@@ -7,9 +7,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-// exception_ptr has not been implemented on Windows
-// XFAIL: LIBCXX-WINDOWS-FIXME
-
 // UNSUPPORTED: libcpp-no-exceptions
 // <exception>
 
@@ -41,7 +38,12 @@ int main()
         }
         catch (const A& a)
         {
+#ifndef _LIBCPP_ABI_MICROSOFT
             assert(A::constructed == 1);
+#else
+            // On Windows exception_ptr copies the exception
+            assert(A::constructed == 2);
+#endif
             assert(p != nullptr);
             p = nullptr;
             assert(p == nullptr);
@@ -50,4 +52,5 @@ int main()
         }
         assert(A::constructed == 0);
     }
+    assert(A::constructed == 0);
 }
diff --git a/libcxx/test/std/language.support/support.exception/propagation/rethrow_exception.pass.cpp b/libcxx/test/std/language.support/support.exception/propagation/rethrow_exception.pass.cpp
index 7d27eee6689..37ffb5be506 100644
--- a/libcxx/test/std/language.support/support.exception/propagation/rethrow_exception.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/propagation/rethrow_exception.pass.cpp
@@ -7,9 +7,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-// exception_ptr has not been implemented on Windows
-// XFAIL: LIBCXX-WINDOWS-FIXME
-
 // UNSUPPORTED: libcpp-no-exceptions
 // <exception>
 
@@ -49,7 +46,12 @@ int main()
         }
         catch (const A& a)
         {
+#ifndef _LIBCPP_ABI_MICROSOFT
             assert(A::constructed == 1);
+#else
+            // On Windows the exception_ptr copies the exception
+            assert(A::constructed == 2);
+#endif
             assert(p != nullptr);
             p = nullptr;
             assert(p == nullptr);
@@ -58,4 +60,5 @@ int main()
         }
         assert(A::constructed == 0);
     }
+    assert(A::constructed == 0);
 }