[ObjC] Make C++ triviality type traits available to non-trivial C

structs.

r326307 and r327870 made changes that allowed using non-trivial C
structs with fields qualified with __strong or __weak. This commit makes
the following C++ triviality type traits available to non-trivial C
structs:

__has_trivial_assign
__has_trivial_move_assign
__has_trivial_copy
__has_trivial_move_constructor
__has_trivial_constructor
__has_trivial_destructor

rdar://problem/33599681

Differential Revision: https://reviews.llvm.org/D44913

llvm-svn: 328680

clang/include/clang/Basic/TokenKinds.def

@@ -433,12 +433,12 @@ TYPE_TRAIT_1(__has_nothrow_assign, HasNothrowAssign, KEYCXX)
 TYPE_TRAIT_1(__has_nothrow_move_assign, HasNothrowMoveAssign, KEYCXX)
 TYPE_TRAIT_1(__has_nothrow_copy, HasNothrowCopy, KEYCXX)
 TYPE_TRAIT_1(__has_nothrow_constructor, HasNothrowConstructor, KEYCXX)
-TYPE_TRAIT_1(__has_trivial_assign, HasTrivialAssign, KEYCXX)
-TYPE_TRAIT_1(__has_trivial_move_assign, HasTrivialMoveAssign, KEYCXX)
-TYPE_TRAIT_1(__has_trivial_copy, HasTrivialCopy, KEYCXX)
-TYPE_TRAIT_1(__has_trivial_constructor, HasTrivialDefaultConstructor, KEYCXX)
-TYPE_TRAIT_1(__has_trivial_move_constructor, HasTrivialMoveConstructor, KEYCXX)
-TYPE_TRAIT_1(__has_trivial_destructor, HasTrivialDestructor, KEYCXX)
+TYPE_TRAIT_1(__has_trivial_assign, HasTrivialAssign, KEYALL)
+TYPE_TRAIT_1(__has_trivial_move_assign, HasTrivialMoveAssign, KEYALL)
+TYPE_TRAIT_1(__has_trivial_copy, HasTrivialCopy, KEYALL)
+TYPE_TRAIT_1(__has_trivial_constructor, HasTrivialDefaultConstructor, KEYALL)
+TYPE_TRAIT_1(__has_trivial_move_constructor, HasTrivialMoveConstructor, KEYALL)
+TYPE_TRAIT_1(__has_trivial_destructor, HasTrivialDestructor, KEYALL)
 TYPE_TRAIT_1(__has_virtual_destructor, HasVirtualDestructor, KEYCXX)
 TYPE_TRAIT_1(__is_abstract, IsAbstract, KEYCXX)
 TYPE_TRAIT_1(__is_aggregate, IsAggregate, KEYCXX)

clang/lib/Sema/SemaExprCXX.cpp

@@ -4513,6 +4513,8 @@ static bool EvaluateUnaryTypeTrait(Sema &Self, TypeTrait UTT,
     // does not correctly compute triviality in the presence of multiple special
     // members of the same kind. Revisit this once the g++ bug is fixed.
   case UTT_HasTrivialDefaultConstructor:
+    if (T.isNonTrivialToPrimitiveDefaultInitialize())
+      return false;
     // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
     //   If __is_pod (type) is true then the trait is true, else if type is
     //   a cv class or union type (or array thereof) with a trivial default
@@ -4524,6 +4526,8 @@ static bool EvaluateUnaryTypeTrait(Sema &Self, TypeTrait UTT,
              !RD->hasNonTrivialDefaultConstructor();
     return false;
   case UTT_HasTrivialMoveConstructor:
+    if (T.isNonTrivialToPrimitiveDestructiveMove())
+      return false;
     //  This trait is implemented by MSVC 2012 and needed to parse the
     //  standard library headers. Specifically this is used as the logic
     //  behind std::is_trivially_move_constructible (20.9.4.3).
@@ -4533,6 +4537,8 @@ static bool EvaluateUnaryTypeTrait(Sema &Self, TypeTrait UTT,
       return RD->hasTrivialMoveConstructor() && !RD->hasNonTrivialMoveConstructor();
     return false;
   case UTT_HasTrivialCopy:
+    if (T.isNonTrivialToPrimitiveCopy())
+      return false;
     // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
     //   If __is_pod (type) is true or type is a reference type then
     //   the trait is true, else if type is a cv class or union type
@@ -4545,6 +4551,8 @@ static bool EvaluateUnaryTypeTrait(Sema &Self, TypeTrait UTT,
              !RD->hasNonTrivialCopyConstructor();
     return false;
   case UTT_HasTrivialMoveAssign:
+    if (T.isNonTrivialToPrimitiveDestructiveMove())
+      return false;
     //  This trait is implemented by MSVC 2012 and needed to parse the
     //  standard library headers. Specifically it is used as the logic
     //  behind std::is_trivially_move_assignable (20.9.4.3)
@@ -4554,6 +4562,8 @@ static bool EvaluateUnaryTypeTrait(Sema &Self, TypeTrait UTT,
       return RD->hasTrivialMoveAssignment() && !RD->hasNonTrivialMoveAssignment();
     return false;
   case UTT_HasTrivialAssign:
+    if (T.isNonTrivialToPrimitiveCopy())
+      return false;
     // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
     //   If type is const qualified or is a reference type then the
     //   trait is false. Otherwise if __is_pod (type) is true then the
@@ -4624,6 +4634,8 @@ static bool EvaluateUnaryTypeTrait(Sema &Self, TypeTrait UTT,
     return true;
 
   case UTT_HasTrivialDestructor:
+    if (T.isDestructedType() == QualType::DK_nontrivial_c_struct)
+      return false;
     // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
     //   If __is_pod (type) is true or type is a reference type
     //   then the trait is true, else if type is a cv class or union

clang/test/SemaObjC/non-trivial-struct-traits.m

@@ -0,0 +1,25 @@
+// RUN: %clang_cc1 -fsyntax-only -fobjc-arc -verify %s
+
+// expected-no-diagnostics
+
+struct Trivial {
+  int x;
+};
+
+struct NonTrivial {
+  id x;
+};
+
+int trivial_assign[__has_trivial_assign(struct Trivial) ? 1 : -1];
+int trivial_move_assign[__has_trivial_move_assign(struct Trivial) ? 1 : -1];
+int trivial_copy_constructor[__has_trivial_copy(struct Trivial) ? 1 : -1];
+int trivial_move_constructor[__has_trivial_move_constructor(struct Trivial) ? 1 : -1];
+int trivial_constructor[__has_trivial_constructor(struct Trivial) ? 1 : -1];
+int trivial_destructor[__has_trivial_destructor(struct Trivial) ? 1 : -1];
+
+int non_trivial_assign[__has_trivial_assign(struct NonTrivial) ? -1 : 1];
+int non_trivial_move_assign[__has_trivial_move_assign(struct NonTrivial) ? -1 : 1];
+int non_trivial_copy_constructor[__has_trivial_copy(struct NonTrivial) ? -1 : 1];
+int non_trivial_move_constructor[__has_trivial_move_constructor(struct NonTrivial) ? -1 : 1];
+int non_trivial_constructor[__has_trivial_constructor(struct NonTrivial) ? -1 : 1];
+int non_trivial_destructor[__has_trivial_destructor(struct NonTrivial) ? -1 : 1];