diff --git a/lib/Transforms/InstCombine/InstCombineCalls.cpp b/lib/Transforms/InstCombine/InstCombineCalls.cpp
index 43419eb9fc0..e501ddc4b85 100644
--- a/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ b/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -334,17 +334,21 @@ Instruction *InstCombiner::visitCallInst(CallInst &CI) {
       // Make sure we're not a constant offset from an external
       // global.
       Value *Operand = GEP->getPointerOperand();
+      Operand = Operand->stripPointerCasts();
       if (GlobalVariable *GV = dyn_cast<GlobalVariable>(Operand))
         if (!GV->hasDefinitiveInitializer()) break;
       
-      // Get what we're pointing to and its size.
-      const PointerType *PT = 
+      // Get what we're pointing to and its size. 
+      const PointerType *BaseType = 
         cast<PointerType>(Operand->getType());
-      size_t Size = TD->getTypeAllocSize(PT->getElementType());
+      size_t Size = TD->getTypeAllocSize(BaseType->getElementType());
       
-      // Get the current byte offset into the thing.
+      // Get the current byte offset into the thing. Use the original
+      // operand in case we're looking through a bitcast.
       SmallVector<Value*, 8> Ops(CE->op_begin()+1, CE->op_end());
-      size_t Offset = TD->getIndexedOffset(PT, &Ops[0], Ops.size());
+      const PointerType *OffsetType =
+        cast<PointerType>(GEP->getPointerOperand()->getType());
+      size_t Offset = TD->getIndexedOffset(OffsetType, &Ops[0], Ops.size());
 
       assert(Size >= Offset);
       
diff --git a/test/Transforms/InstCombine/objsize.ll b/test/Transforms/InstCombine/objsize.ll
index 646baa0de06..dbc7d31c392 100644
--- a/test/Transforms/InstCombine/objsize.ll
+++ b/test/Transforms/InstCombine/objsize.ll
@@ -63,4 +63,13 @@ entry:
   unreachable
 }
 
+@.str5 = private constant [9 x i32] [i32 97, i32 98, i32 99, i32 100, i32 0, i32
+ 101, i32 102, i32 103, i32 0], align 4 ;
+define i32 @test2() nounwind {
+; CHECK: @test2
+; CHECK-NEXT: ret i32 34
+  %1 = call i32 @llvm.objectsize.i32(i8* getelementptr (i8* bitcast ([9 x i32]* @.str5 to i8*), i32 2), i1 false)
+  ret i32 %1
+}
+
 declare i32 @llvm.objectsize.i32(i8*, i1) nounwind readonly
\ No newline at end of file