Implement AST, semantics, and CodeGen for C++ pseudo-destructor
expressions, e.g.,
p->~T()
when p is a pointer to a scalar type.
We don't currently diagnose errors when pseudo-destructor expressions
are used in any way other than by forming a call.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@81009 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 720217a..58d6a0d 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -1998,7 +1998,7 @@
Base = MaybeConvertParenListExprToParenExpr(S, move(Base));
Expr *BaseExpr = Base.takeAs<Expr>();
- assert(BaseExpr && "no record expression");
+ assert(BaseExpr && "no base expression");
// Perform default conversions.
DefaultFunctionArrayConversion(BaseExpr);
@@ -2230,6 +2230,47 @@
<< MemberName << int(OpKind == tok::arrow));
}
+ // Handle pseudo-destructors (C++ [expr.pseudo]). Since anything referring
+ // into a record type was handled above, any destructor we see here is a
+ // pseudo-destructor.
+ if (MemberName.getNameKind() == DeclarationName::CXXDestructorName) {
+ // C++ [expr.pseudo]p2:
+ // The left hand side of the dot operator shall be of scalar type. The
+ // left hand side of the arrow operator shall be of pointer to scalar
+ // type.
+ if (!BaseType->isScalarType())
+ return Owned(Diag(OpLoc, diag::err_pseudo_dtor_base_not_scalar)
+ << BaseType << BaseExpr->getSourceRange());
+
+ // [...] The type designated by the pseudo-destructor-name shall be the
+ // same as the object type.
+ if (!MemberName.getCXXNameType()->isDependentType() &&
+ !Context.hasSameUnqualifiedType(BaseType, MemberName.getCXXNameType()))
+ return Owned(Diag(OpLoc, diag::err_pseudo_dtor_type_mismatch)
+ << BaseType << MemberName.getCXXNameType()
+ << BaseExpr->getSourceRange() << SourceRange(MemberLoc));
+
+ // [...] Furthermore, the two type-names in a pseudo-destructor-name of
+ // the form
+ //
+ // ::[opt] nested-name-specifier[opt] type-name :: ̃ type-name
+ //
+ // shall designate the same scalar type.
+ //
+ // FIXME: DPG can't see any way to trigger this particular clause, so it
+ // isn't checked here.
+
+ // FIXME: We've lost the precise spelling of the type by going through
+ // DeclarationName. Can we do better?
+ return Owned(new (Context) CXXPseudoDestructorExpr(Context, BaseExpr,
+ OpKind == tok::arrow,
+ OpLoc,
+ (NestedNameSpecifier *)(SS? SS->getScopeRep() : 0),
+ SS? SS->getRange() : SourceRange(),
+ MemberName.getCXXNameType(),
+ MemberLoc));
+ }
+
// Handle properties on ObjC 'Class' types.
if (OpKind == tok::period && BaseType->isObjCClassType()) {
// Also must look for a getter name which uses property syntax.
@@ -2684,6 +2725,25 @@
DeclarationName UnqualifiedName;
if (getLangOptions().CPlusPlus) {
+ // If this is a pseudo-destructor expression, build the call immediately.
+ if (isa<CXXPseudoDestructorExpr>(Fn)) {
+ if (NumArgs > 0) {
+ // Pseudo-destructor calls should not have any arguments.
+ Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args)
+ << CodeModificationHint::CreateRemoval(
+ SourceRange(Args[0]->getLocStart(),
+ Args[NumArgs-1]->getLocEnd()));
+
+ for (unsigned I = 0; I != NumArgs; ++I)
+ Args[I]->Destroy(Context);
+
+ NumArgs = 0;
+ }
+
+ return Owned(new (Context) CallExpr(Context, Fn, 0, 0, Context.VoidTy,
+ RParenLoc));
+ }
+
// Determine whether this is a dependent call inside a C++ template,
// in which case we won't do any semantic analysis now.
// FIXME: Will need to cache the results of name lookup (including ADL) in