Downgrade the invalid offsetof error to a warning.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@70634 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Basic/DiagnosticGroups.td b/include/clang/Basic/DiagnosticGroups.td
index 8e9296d..bee24ad 100644
--- a/include/clang/Basic/DiagnosticGroups.td
+++ b/include/clang/Basic/DiagnosticGroups.td
@@ -82,6 +82,7 @@
 def : DiagGroup<"strict-overflow=2">;
 def : DiagGroup<"strict-overflow">;
 
+def InvalidOffsetof : DiagGroup<"invalid-offsetof">;
 def : DiagGroup<"strict-prototypes">;
 def : DiagGroup<"strict-selector-match">;
 def Switch         : DiagGroup<"switch">;
diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 72689b9..2900c3d 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -936,7 +936,8 @@
 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_offsetof_non_pod_type : Warning<"offset of on non-POD type %0">,
+  InGroup<InvalidOffsetof>;
 
 def warn_floatingpoint_eq : Warning<
   "comparing floating point with == or != is unsafe">,
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 33d308e..dc058b2 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -4777,9 +4777,9 @@
       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());
+          ExprError(Diag(BuiltinLoc, diag::warn_offsetof_non_pod_type)
+            << SourceRange(CompPtr[0].LocStart, OC.LocEnd)
+            << Res->getType());
       }
       
       FieldDecl *MemberDecl
diff --git a/test/SemaCXX/offsetof.cpp b/test/SemaCXX/offsetof.cpp
index 726dc7e..c8a3d3d 100644
--- a/test/SemaCXX/offsetof.cpp
+++ b/test/SemaCXX/offsetof.cpp
@@ -10,6 +10,6 @@
 };
 
 void f() {
-  int i = __builtin_offsetof(P, fieldThatPointsToANonPODType.m); // expected-error{{offset of on non-POD type 'struct P'}}
+  int i = __builtin_offsetof(P, fieldThatPointsToANonPODType.m); // expected-warning{{offset of on non-POD type 'struct P'}}
 }