From 6d7f149b0bff12e8f74c372e50b6e9a9ea980425 Mon Sep 17 00:00:00 2001
From: Anders Carlsson <andersca@mac.com>
Date: Fri, 1 May 2009 23:20:30 +0000
Subject: [PATCH] It's an error to call offsetof on a non-POD type.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@70595 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/clang/Basic/DiagnosticSemaKinds.td |  2 ++
 lib/Sema/SemaExpr.cpp                      |  7 +++++++
 test/SemaCXX/offsetof.cpp                  | 15 +++++++++++++++
 3 files changed, 24 insertions(+)
 create mode 100644 test/SemaCXX/offsetof.cpp

diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 0cbbfc750b..c9bdf13b30 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -936,6 +936,8 @@ def err_offsetof_record_type : Error<
 def err_offsetof_array_type : Error<"offsetof requires array type, %0 invalid">;
 def ext_offsetof_extended_field_designator : Extension<
   "using extended field designator is an extension">;
+def err_offsetof_non_pod_type : Error<"offset of on non-POD type %0">;
+
 def warn_floatingpoint_eq : Warning<
   "comparing floating point with == or != is unsafe">,
   InGroup<DiagGroup<"float-equal">>, DefaultIgnore;
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index bf9947a5e2..3442cc1db9 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -4761,6 +4761,13 @@ Sema::OwningExprResult Sema::ActOnBuiltinOffsetOf(Scope *S,
 
       // Get the decl corresponding to this.
       RecordDecl *RD = RC->getDecl();
+      if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) {
+        if (!CRD->isPOD())
+          return ExprError(Diag(BuiltinLoc, diag::err_offsetof_non_pod_type)
+                   << SourceRange(CompPtr[0].LocStart, OC.LocEnd)
+                   << Res->getType());
+      }
+      
       FieldDecl *MemberDecl
         = dyn_cast_or_null<FieldDecl>(LookupQualifiedName(RD, OC.U.IdentInfo,
                                                           LookupMemberName)
diff --git a/test/SemaCXX/offsetof.cpp b/test/SemaCXX/offsetof.cpp
new file mode 100644
index 0000000000..726dc7e527
--- /dev/null
+++ b/test/SemaCXX/offsetof.cpp
@@ -0,0 +1,15 @@
+// RUN: clang-cc -fsyntax-only -verify %s
+
+struct NonPOD {
+  virtual void f();
+  int m;
+};
+
+struct P {
+  NonPOD fieldThatPointsToANonPODType;
+};
+
+void f() {
+  int i = __builtin_offsetof(P, fieldThatPointsToANonPODType.m); // expected-error{{offset of on non-POD type 'struct P'}}
+}
+
-- 
2.40.0