When applying 'delete' on a pointer-to-array type match GCC and EDG behavior and treat it as 'delete[]'.

Also offer a fix-it hint adding '[]'.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@113778 91177308-0d34-0410-b5e6-96231b3b80d8

7 files changed, 40 insertions, 5 deletions

diff --git a/include/clang/AST/ExprCXX.h b/include/clang/AST/ExprCXX.h
index 219e2f982b..2ad7285f44 100644
--- a/include/clang/AST/ExprCXX.h
+++ b/include/clang/AST/ExprCXX.h
@@ -1107,6 +1107,10 @@ class CXXDeleteExpr : public Expr {
   bool GlobalDelete : 1;
   // Is this the array form of delete, i.e. "delete[]"?
   bool ArrayForm : 1;
+  // ArrayFormAsWritten can be different from ArrayForm if 'delete' is applied
+  // to pointer-to-array type (ArrayFormAsWritten will be false while ArrayForm
+  // will be true).
+  bool ArrayFormAsWritten : 1;
   // Points to the operator delete overload that is used. Could be a member.
   FunctionDecl *OperatorDelete;
   // The pointer expression to be deleted.
@@ -1115,15 +1119,17 @@ class CXXDeleteExpr : public Expr {
   SourceLocation Loc;
 public:
   CXXDeleteExpr(QualType ty, bool globalDelete, bool arrayForm,
-                FunctionDecl *operatorDelete, Expr *arg, SourceLocation loc)
+                bool arrayFormAsWritten, FunctionDecl *operatorDelete,
+                Expr *arg, SourceLocation loc)
     : Expr(CXXDeleteExprClass, ty, false, false), GlobalDelete(globalDelete),
-      ArrayForm(arrayForm), OperatorDelete(operatorDelete), Argument(arg),
-      Loc(loc) { }
+      ArrayForm(arrayForm), ArrayFormAsWritten(arrayFormAsWritten),
+      OperatorDelete(operatorDelete), Argument(arg), Loc(loc) { }
   explicit CXXDeleteExpr(EmptyShell Shell)
     : Expr(CXXDeleteExprClass, Shell), OperatorDelete(0), Argument(0) { }
 
   bool isGlobalDelete() const { return GlobalDelete; }
   bool isArrayForm() const { return ArrayForm; }
+  bool isArrayFormAsWritten() const { return ArrayFormAsWritten; }
 
   FunctionDecl *getOperatorDelete() const { return OperatorDelete; }
 
diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index ab16675986..9edceb820c 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -2448,6 +2448,8 @@ def warn_delete_incomplete : Warning<
   "deleting pointer to incomplete type %0 may cause undefined behaviour">;
 def err_delete_incomplete_class_type : Warning<
   "deleting incomplete class type %0; no conversions to pointer type">;
+def warn_delete_array_type : Warning<
+  "'delete' applied to a pointer-to-array type %0 treated as delete[]">;
 def err_no_suitable_delete_member_function_found : Error<
   "no suitable member %0 in %1">;
 def err_ambiguous_suitable_delete_member_function_found : Error<
diff --git a/lib/Sema/SemaExprCXX.cpp b/lib/Sema/SemaExprCXX.cpp
index 382e9bb185..db287515ce 100644
--- a/lib/Sema/SemaExprCXX.cpp
+++ b/lib/Sema/SemaExprCXX.cpp
@@ -1438,6 +1438,7 @@ Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal,
   // DR599 amends "pointer type" to "pointer to object type" in both cases.
 
   FunctionDecl *OperatorDelete = 0;
+  bool ArrayFormAsWritten = ArrayForm;
 
   if (!Ex->isTypeDependent()) {
     QualType Type = Ex->getType();
@@ -1514,7 +1515,14 @@ Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal,
     //   of the delete-expression. ]
     ImpCastExprToType(Ex, Context.getPointerType(Context.VoidTy), 
                       CK_NoOp);
-    
+
+    if (Pointee->isArrayType() && !ArrayForm) {
+      Diag(StartLoc, diag::warn_delete_array_type)
+          << Type << Ex->getSourceRange()
+          << FixItHint::CreateInsertion(PP.getLocForEndOfToken(StartLoc), "[]");
+      ArrayForm = true;
+    }
+
     DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName(
                                       ArrayForm ? OO_Array_Delete : OO_Delete);
 
@@ -1548,7 +1556,8 @@ Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal,
   }
 
   return Owned(new (Context) CXXDeleteExpr(Context.VoidTy, UseGlobal, ArrayForm,
-                                           OperatorDelete, Ex, StartLoc));
+                                           ArrayFormAsWritten, OperatorDelete,
+                                           Ex, StartLoc));
 }
 
 /// \brief Check the use of the given variable as a C++ condition in an if,
diff --git a/lib/Serialization/ASTReaderStmt.cpp b/lib/Serialization/ASTReaderStmt.cpp
index e53bf716a8..a6da3c7296 100644
--- a/lib/Serialization/ASTReaderStmt.cpp
+++ b/lib/Serialization/ASTReaderStmt.cpp
@@ -1112,6 +1112,7 @@ void ASTStmtReader::VisitCXXDeleteExpr(CXXDeleteExpr *E) {
   VisitExpr(E);
   E->GlobalDelete = Record[Idx++];
   E->ArrayForm = Record[Idx++];
+  E->ArrayFormAsWritten = Record[Idx++];
   E->OperatorDelete = cast_or_null<FunctionDecl>(Reader.GetDecl(Record[Idx++]));
   E->Argument = Reader.ReadSubExpr();
   E->Loc = Reader.ReadSourceLocation(Record, Idx);
diff --git a/lib/Serialization/ASTWriterStmt.cpp b/lib/Serialization/ASTWriterStmt.cpp
index b9a22842b9..3701e0c146 100644
--- a/lib/Serialization/ASTWriterStmt.cpp
+++ b/lib/Serialization/ASTWriterStmt.cpp
@@ -1121,6 +1121,7 @@ void ASTStmtWriter::VisitCXXDeleteExpr(CXXDeleteExpr *E) {
   VisitExpr(E);
   Record.push_back(E->isGlobalDelete());
   Record.push_back(E->isArrayForm());
+  Record.push_back(E->isArrayFormAsWritten());
   Writer.AddDeclRef(E->getOperatorDelete(), Record);
   Writer.AddStmt(E->getArgument());
   Writer.AddSourceLocation(E->getSourceRange().getBegin(), Record);
diff --git a/test/CodeGenCXX/delete.cpp b/test/CodeGenCXX/delete.cpp
index 1f52a783e6..b8726a863e 100644
--- a/test/CodeGenCXX/delete.cpp
+++ b/test/CodeGenCXX/delete.cpp
@@ -105,3 +105,10 @@ namespace test2 {
     delete [] b;
   }
 }
+
+namespace test3 {
+  void f(int a[10][20]) {
+    // CHECK: call void @_ZdaPv(i8*
+    delete a;
+  }
+}
diff --git a/test/SemaCXX/delete.cpp b/test/SemaCXX/delete.cpp
new file mode 100644
index 0000000000..4567888a37
--- /dev/null
+++ b/test/SemaCXX/delete.cpp
@@ -0,0 +1,9 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+// RUN: cp %s %t
+// RUN: %clang_cc1 -fixit -x c++ %t
+// RUN: FileCheck -input-file=%t %s
+
+void f(int a[10][20]) {
+  // CHECK: delete[] a;
+  delete a; // expected-warning {{'delete' applied to a pointer-to-array type}}
+}