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authorGravatar Abseil Team <absl-team@google.com>2019-12-04 14:13:43 -0800
committerGravatar Mark Barolak <mbar@google.com>2019-12-05 11:46:50 -0500
commitd659fe54b35ab9b8e35c72e50a4b8814167d5a84 (patch)
treedd21b4e5d1d3980a6a38c5a445853d4e1b744b90 /absl/meta
parenta4b757b5d42694306a9de853cee0a5fba9c7bbe9 (diff)
Export of internal Abseil changes
-- c385118b3ef0528d150bfe7aeeb63e77f9e463cd by Matt Calabrese <calabrese@google.com>: Internal-only Archetype generation for testing generic code with user-defined types of various properties. PiperOrigin-RevId: 283833099 -- 4ccf340d3b295aa5b796ee5c97128b61d38899ea by Derek Mauro <dmauro@google.com>: Fixes the flags parse_test. Windows doesn't like consecutive path separators. PiperOrigin-RevId: 283614649 -- 5df6d83acb1e49cd1da785cfaf7551f05149f3c9 by Andy Getzendanner <durandal@google.com>: ABSL_INTERNAL_LOG: forward complete __FILE__ to internal_log_function; not just basename. PiperOrigin-RevId: 283406080 GitOrigin-RevId: c385118b3ef0528d150bfe7aeeb63e77f9e463cd Change-Id: Ib0782354691a73fc40185c3262cfd507085b3393
Diffstat (limited to 'absl/meta')
-rw-r--r--absl/meta/type_traits.h45
-rw-r--r--absl/meta/type_traits_test.cc21
2 files changed, 37 insertions, 29 deletions
diff --git a/absl/meta/type_traits.h b/absl/meta/type_traits.h
index d57a8792..8cd5f043 100644
--- a/absl/meta/type_traits.h
+++ b/absl/meta/type_traits.h
@@ -41,10 +41,20 @@
#include "absl/base/config.h"
+// MSVC constructibility traits do not detect destructor properties and so our
+// implementations should not use them as a source-of-truth.
+#if defined(_MSC_VER) && !defined(__clang__) && !defined(__GNUC__)
+#define ABSL_META_INTERNAL_STD_CONSTRUCTION_TRAITS_DONT_CHECK_DESTRUCTION 1
+#endif
+
namespace absl {
// Defined and documented later on in this file.
template <typename T>
+struct is_trivially_destructible;
+
+// Defined and documented later on in this file.
+template <typename T>
struct is_trivially_move_assignable;
namespace type_traits_internal {
@@ -66,6 +76,20 @@ union SingleMemberUnion {
#endif // defined(_MSC_VER) && !defined(__GNUC__)
template <class T>
+struct IsTriviallyMoveConstructibleObject
+ : std::integral_constant<
+ bool, std::is_move_constructible<
+ type_traits_internal::SingleMemberUnion<T>>::value &&
+ absl::is_trivially_destructible<T>::value> {};
+
+template <class T>
+struct IsTriviallyCopyConstructibleObject
+ : std::integral_constant<
+ bool, std::is_copy_constructible<
+ type_traits_internal::SingleMemberUnion<T>>::value &&
+ absl::is_trivially_destructible<T>::value> {};
+
+template <class T>
struct IsTriviallyMoveAssignableReference : std::false_type {};
template <class T>
@@ -323,7 +347,9 @@ struct is_trivially_default_constructible
: std::integral_constant<bool, __has_trivial_constructor(T) &&
std::is_default_constructible<T>::value &&
is_trivially_destructible<T>::value> {
-#ifdef ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE
+#if defined(ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE) && \
+ !defined( \
+ ABSL_META_INTERNAL_STD_CONSTRUCTION_TRAITS_DONT_CHECK_DESTRUCTION)
private:
static constexpr bool compliant =
std::is_trivially_default_constructible<T>::value ==
@@ -354,10 +380,11 @@ template <typename T>
struct is_trivially_move_constructible
: std::conditional<
std::is_object<T>::value && !std::is_array<T>::value,
- std::is_move_constructible<
- type_traits_internal::SingleMemberUnion<T>>,
+ type_traits_internal::IsTriviallyMoveConstructibleObject<T>,
std::is_reference<T>>::type::type {
-#ifdef ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE
+#if defined(ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE) && \
+ !defined( \
+ ABSL_META_INTERNAL_STD_CONSTRUCTION_TRAITS_DONT_CHECK_DESTRUCTION)
private:
static constexpr bool compliant =
std::is_trivially_move_constructible<T>::value ==
@@ -388,10 +415,11 @@ template <typename T>
struct is_trivially_copy_constructible
: std::conditional<
std::is_object<T>::value && !std::is_array<T>::value,
- std::is_copy_constructible<
- type_traits_internal::SingleMemberUnion<T>>,
+ type_traits_internal::IsTriviallyCopyConstructibleObject<T>,
std::is_lvalue_reference<T>>::type::type {
-#ifdef ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE
+#if defined(ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE) && \
+ !defined( \
+ ABSL_META_INTERNAL_STD_CONSTRUCTION_TRAITS_DONT_CHECK_DESTRUCTION)
private:
static constexpr bool compliant =
std::is_trivially_copy_constructible<T>::value ==
@@ -423,7 +451,8 @@ struct is_trivially_copy_constructible
template <typename T>
struct is_trivially_move_assignable
: std::conditional<
- std::is_object<T>::value && !std::is_array<T>::value,
+ std::is_object<T>::value && !std::is_array<T>::value &&
+ std::is_move_assignable<T>::value,
std::is_move_assignable<type_traits_internal::SingleMemberUnion<T>>,
type_traits_internal::IsTriviallyMoveAssignableReference<T>>::type::
type {
diff --git a/absl/meta/type_traits_test.cc b/absl/meta/type_traits_test.cc
index 6fbb42f8..1aafd0d4 100644
--- a/absl/meta/type_traits_test.cc
+++ b/absl/meta/type_traits_test.cc
@@ -347,21 +347,6 @@ class Base {
virtual ~Base() {}
};
-// In GCC/Clang, std::is_trivially_constructible requires that the destructor is
-// trivial. However, MSVC doesn't require that. This results in different
-// behavior when checking is_trivially_constructible on any type with
-// nontrivial destructor. Since absl::is_trivially_default_constructible and
-// absl::is_trivially_copy_constructible both follows Clang/GCC's interpretation
-// and check is_trivially_destructible, it results in inconsistency with
-// std::is_trivially_xxx_constructible on MSVC. This macro is used to work
-// around this issue in test. In practice, a trivially constructible type
-// should also be trivially destructible.
-// GCC bug 51452: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=51452
-// LWG issue 2116: http://cplusplus.github.io/LWG/lwg-active.html#2116
-#ifndef _MSC_VER
-#define ABSL_TRIVIALLY_CONSTRUCTIBLE_VERIFY_TRIVIALLY_DESTRUCTIBLE 1
-#endif
-
// Old versions of libc++, around Clang 3.5 to 3.6, consider deleted destructors
// as also being trivial. With the resolution of CWG 1928 and CWG 1734, this
// is no longer considered true and has thus been amended.
@@ -499,11 +484,9 @@ TEST(TypeTraitsTest, TestTrivialDefaultCtor) {
EXPECT_FALSE(
absl::is_trivially_default_constructible<DeletedDefaultCtor>::value);
-#ifdef ABSL_TRIVIALLY_CONSTRUCTIBLE_VERIFY_TRIVIALLY_DESTRUCTIBLE
// types with nontrivial destructor are nontrivial
EXPECT_FALSE(
absl::is_trivially_default_constructible<NontrivialDestructor>::value);
-#endif
// types with vtables
EXPECT_FALSE(absl::is_trivially_default_constructible<Base>::value);
@@ -607,11 +590,9 @@ TEST(TypeTraitsTest, TestTrivialMoveCtor) {
EXPECT_FALSE(
absl::is_trivially_move_constructible<NonCopyableOrMovable>::value);
-#ifdef ABSL_TRIVIALLY_CONSTRUCTIBLE_VERIFY_TRIVIALLY_DESTRUCTIBLE
// type with nontrivial destructor are nontrivial move construbtible
EXPECT_FALSE(
absl::is_trivially_move_constructible<NontrivialDestructor>::value);
-#endif
// types with vtables
EXPECT_FALSE(absl::is_trivially_move_constructible<Base>::value);
@@ -682,11 +663,9 @@ TEST(TypeTraitsTest, TestTrivialCopyCtor) {
EXPECT_FALSE(
absl::is_trivially_copy_constructible<NonCopyableOrMovable>::value);
-#ifdef ABSL_TRIVIALLY_CONSTRUCTIBLE_VERIFY_TRIVIALLY_DESTRUCTIBLE
// type with nontrivial destructor are nontrivial copy construbtible
EXPECT_FALSE(
absl::is_trivially_copy_constructible<NontrivialDestructor>::value);
-#endif
// types with vtables
EXPECT_FALSE(absl::is_trivially_copy_constructible<Base>::value);