Properly compute triviality for explicitly-defaulted or deleted special members.
Remove pre-standard restriction on explicitly-defaulted copy constructors with
'incorrect' parameter types, and instead just make those special members
non-trivial as the standard requires.
This required making CXXRecordDecl correctly handle classes which have both a
trivial and a non-trivial special member of the same kind.
This also fixes PR13217 by reimplementing DiagnoseNontrivial in terms of the
new triviality computation technology.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@169667 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaExprCXX.cpp b/lib/Sema/SemaExprCXX.cpp
index b785e54..5345e8d 100644
--- a/lib/Sema/SemaExprCXX.cpp
+++ b/lib/Sema/SemaExprCXX.cpp
@@ -3058,6 +3058,13 @@
//
// 1: http://gcc.gnu/.org/onlinedocs/gcc/Type-Traits.html
// 2: http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
+ //
+ // Note that these builtins do not behave as documented in g++: if a class
+ // has both a trivial and a non-trivial special member of a particular kind,
+ // they return false! For now, we emulate this behavior.
+ // FIXME: This appears to be a g++ bug: more complex cases reveal that it
+ // 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:
// http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
// If __is_pod (type) is true then the trait is true, else if type is
@@ -3065,9 +3072,9 @@
// constructor ([class.ctor]) then the trait is true, else it is false.
if (T.isPODType(Self.Context))
return true;
- if (const RecordType *RT =
- C.getBaseElementType(T)->getAs<RecordType>())
- return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialDefaultConstructor();
+ if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
+ return RD->hasTrivialDefaultConstructor() &&
+ !RD->hasNonTrivialDefaultConstructor();
return false;
case UTT_HasTrivialCopy:
// http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
@@ -3077,8 +3084,9 @@
// is true, else it is false.
if (T.isPODType(Self.Context) || T->isReferenceType())
return true;
- if (const RecordType *RT = T->getAs<RecordType>())
- return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialCopyConstructor();
+ if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
+ return RD->hasTrivialCopyConstructor() &&
+ !RD->hasNonTrivialCopyConstructor();
return false;
case UTT_HasTrivialAssign:
// http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
@@ -3093,12 +3101,13 @@
// errors if the copy assignment operator is actually used, q.v.
// [class.copy]p12).
- if (C.getBaseElementType(T).isConstQualified())
+ if (T.isConstQualified())
return false;
if (T.isPODType(Self.Context))
return true;
- if (const RecordType *RT = T->getAs<RecordType>())
- return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialCopyAssignment();
+ if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
+ return RD->hasTrivialCopyAssignment() &&
+ !RD->hasNonTrivialCopyAssignment();
return false;
case UTT_HasTrivialDestructor:
// http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
@@ -3115,9 +3124,8 @@
T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing)
return true;
- if (const RecordType *RT =
- C.getBaseElementType(T)->getAs<RecordType>())
- return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialDestructor();
+ if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
+ return RD->hasTrivialDestructor();
return false;
// TODO: Propagate nothrowness for implicitly declared special members.
case UTT_HasNothrowAssign:
@@ -3134,9 +3142,8 @@
return false;
if (T.isPODType(Self.Context) || T->isObjCLifetimeType())
return true;
- if (const RecordType *RT = T->getAs<RecordType>()) {
- CXXRecordDecl* RD = cast<CXXRecordDecl>(RT->getDecl());
- if (RD->hasTrivialCopyAssignment())
+ if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) {
+ if (RD->hasTrivialCopyAssignment() && !RD->hasNonTrivialCopyAssignment())
return true;
bool FoundAssign = false;
@@ -3175,9 +3182,9 @@
// false.
if (T.isPODType(C) || T->isReferenceType() || T->isObjCLifetimeType())
return true;
- if (const RecordType *RT = T->getAs<RecordType>()) {
- CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
- if (RD->hasTrivialCopyConstructor())
+ if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) {
+ if (RD->hasTrivialCopyConstructor() &&
+ !RD->hasNonTrivialCopyConstructor())
return true;
bool FoundConstructor = false;
@@ -3216,9 +3223,9 @@
// throw an exception then the trait is true, else it is false.
if (T.isPODType(C) || T->isObjCLifetimeType())
return true;
- if (const RecordType *RT = C.getBaseElementType(T)->getAs<RecordType>()) {
- CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
- if (RD->hasTrivialDefaultConstructor())
+ if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) {
+ if (RD->hasTrivialDefaultConstructor() &&
+ !RD->hasNonTrivialDefaultConstructor())
return true;
DeclContext::lookup_const_iterator Con, ConEnd;
@@ -3245,11 +3252,9 @@
// http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
// If type is a class type with a virtual destructor ([class.dtor])
// then the trait is true, else it is false.
- if (const RecordType *Record = T->getAs<RecordType>()) {
- CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl());
+ if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
if (CXXDestructorDecl *Destructor = Self.LookupDestructor(RD))
return Destructor->isVirtual();
- }
return false;
// These type trait expressions are modeled on the specifications for the