diff --git a/lib/CodeGen/CGRecordLayoutBuilder.cpp b/lib/CodeGen/CGRecordLayoutBuilder.cpp
index 2d10b1f..455b929 100644
--- a/lib/CodeGen/CGRecordLayoutBuilder.cpp
+++ b/lib/CodeGen/CGRecordLayoutBuilder.cpp
@@ -88,10 +88,8 @@
   
   AppendBytes(NumBytesToAppend);
   
-  if (!NumBytesToAppend)
-    BitsAvailableInLastField -= FieldSize;
-  else
-    BitsAvailableInLastField = NumBytesToAppend * 8 - FieldSize;
+  BitsAvailableInLastField = 
+    getNextFieldOffsetInBytes() * 8 - (FieldOffset + FieldSize);
 }
 
 bool CGRecordLayoutBuilder::LayoutField(const FieldDecl *D,
diff --git a/test/CodeGen/PR4611-bitfield-layout.c b/test/CodeGen/PR4611-bitfield-layout.c
new file mode 100644
index 0000000..ef698d5
--- /dev/null
+++ b/test/CodeGen/PR4611-bitfield-layout.c
@@ -0,0 +1,6 @@
+// RUN: clang-cc -triple i386-unknown-unknown %s -emit-llvm -o %t &&
+// RUN: grep "struct.object_entry = type <{ i8, i8, i8, i8 }>" %t
+
+struct object_entry {
+       unsigned int type:3, pack_id:16, depth:13;
+} entries;