diff --git a/lib/AST/RecordLayoutBuilder.cpp b/lib/AST/RecordLayoutBuilder.cpp
index 1ea2be41b3bd3a548c1fcb5846d416cf5dd02ebf..02fbcf0a4ad1ad6071c274cf9c050e5092d39291 100644
--- a/lib/AST/RecordLayoutBuilder.cpp
+++ b/lib/AST/RecordLayoutBuilder.cpp
@@ -2091,9 +2091,6 @@ static bool isMsLayout(const RecordDecl* D) {
// one.
// * The last zero size virtual base may be placed at the end of the struct.
// and can potentially alias a zero sized type in the next struct.
-// * If the last field is a non-zero length bitfield, all virtual bases will
-// have extra padding added before them for no obvious reason. The padding
-// has the same number of bits as the type of the bitfield.
// * When laying out empty non-virtual bases, an extra byte of padding is added
// if the non-virtual base before the empty non-virtual base has a vbptr.
// * The ABI attempts to avoid aliasing of zero sized bases by adding padding
@@ -2595,10 +2592,6 @@ void MicrosoftRecordLayoutBuilder::layoutVirtualBases(const CXXRecordDecl *RD) {
const CXXRecordDecl *BaseDecl = I.getType()->getAsCXXRecordDecl();
const ASTRecordLayout &BaseLayout = Context.getASTRecordLayout(BaseDecl);
bool HasVtordisp = HasVtordispSet.count(BaseDecl);
- // If the last field we laid out was a non-zero length bitfield then add
- // some extra padding for no obvious reason.
- if (LastFieldIsNonZeroWidthBitfield)
- Size += CurrentBitfieldSize;
// Insert padding between two bases if the left first one is zero sized or
// contains a zero sized subobject and the right is zero sized or one leads
// with a zero sized base. The padding between virtual bases is 4
diff --git a/test/Layout/ms-x86-bitfields-vbases.cpp b/test/Layout/ms-x86-bitfields-vbases.cpp
index 7cffa8c8e4ac9fba5eace8f6b1231dd47c8e7a3c..5b54596bbb83c89a4b99a85fb1f971da535b75ca 100644
--- a/test/Layout/ms-x86-bitfields-vbases.cpp
+++ b/test/Layout/ms-x86-bitfields-vbases.cpp
@@ -13,17 +13,17 @@ struct A : virtual B0 { char a : 1; };
// CHECK-NEXT: 0 | struct A
// CHECK-NEXT: 0 | (A vbtable pointer)
// CHECK-NEXT: 4 | char a
-// CHECK-NEXT: 12 | struct B0 (virtual base)
-// CHECK-NEXT: 12 | int a
-// CHECK-NEXT: | [sizeof=16, align=4
+// CHECK-NEXT: 8 | struct B0 (virtual base)
+// CHECK-NEXT: 8 | int a
+// CHECK-NEXT: | [sizeof=12, align=4
// CHECK-NEXT: | nvsize=8, nvalign=4]
// CHECK-X64: *** Dumping AST Record Layout
// CHECK-X64: *** Dumping AST Record Layout
// CHECK-X64-NEXT: 0 | struct A
// CHECK-X64-NEXT: 0 | (A vbtable pointer)
// CHECK-X64-NEXT: 8 | char a
-// CHECK-X64-NEXT: 20 | struct B0 (virtual base)
-// CHECK-X64-NEXT: 20 | int a
+// CHECK-X64-NEXT: 16 | struct B0 (virtual base)
+// CHECK-X64-NEXT: 16 | int a
// CHECK-X64-NEXT: | [sizeof=24, align=8
// CHECK-X64-NEXT: | nvsize=16, nvalign=8]
@@ -33,16 +33,16 @@ struct B : virtual B0 { short a : 1; };
// CHECK-NEXT: 0 | struct B
// CHECK-NEXT: 0 | (B vbtable pointer)
// CHECK-NEXT: 4 | short a
-// CHECK-NEXT: 12 | struct B0 (virtual base)
-// CHECK-NEXT: 12 | int a
-// CHECK-NEXT: | [sizeof=16, align=4
+// CHECK-NEXT: 8 | struct B0 (virtual base)
+// CHECK-NEXT: 8 | int a
+// CHECK-NEXT: | [sizeof=12, align=4
// CHECK-NEXT: | nvsize=8, nvalign=4]
// CHECK-X64: *** Dumping AST Record Layout
// CHECK-X64-NEXT: 0 | struct B
// CHECK-X64-NEXT: 0 | (B vbtable pointer)
// CHECK-X64-NEXT: 8 | short a
-// CHECK-X64-NEXT: 20 | struct B0 (virtual base)
-// CHECK-X64-NEXT: 20 | int a
+// CHECK-X64-NEXT: 16 | struct B0 (virtual base)
+// CHECK-X64-NEXT: 16 | int a
// CHECK-X64-NEXT: | [sizeof=24, align=8
// CHECK-X64-NEXT: | nvsize=16, nvalign=8]
@@ -94,22 +94,22 @@ struct E : virtual B0, virtual B1 { long long : 1; };
// CHECK-NEXT: 0 | struct E
// CHECK-NEXT: 0 | (E vbtable pointer)
// CHECK-NEXT: 8 | long long
-// CHECK-NEXT: 24 | struct B0 (virtual base)
-// CHECK-NEXT: 24 | int a
-// CHECK-NEXT: 36 | struct B1 (virtual base)
-// CHECK-NEXT: 36 | int a
-// CHECK-NEXT: | [sizeof=40, align=8
+// CHECK-NEXT: 16 | struct B0 (virtual base)
+// CHECK-NEXT: 16 | int a
+// CHECK-NEXT: 20 | struct B1 (virtual base)
+// CHECK-NEXT: 20 | int a
+// CHECK-NEXT: | [sizeof=24, align=8
// CHECK-NEXT: | nvsize=16, nvalign=8]
// CHECK-X64: *** Dumping AST Record Layout
// CHECK-X64: *** Dumping AST Record Layout
// CHECK-X64-NEXT: 0 | struct E
// CHECK-X64-NEXT: 0 | (E vbtable pointer)
// CHECK-X64-NEXT: 8 | long long
-// CHECK-X64-NEXT: 24 | struct B0 (virtual base)
-// CHECK-X64-NEXT: 24 | int a
-// CHECK-X64-NEXT: 36 | struct B1 (virtual base)
-// CHECK-X64-NEXT: 36 | int a
-// CHECK-X64-NEXT: | [sizeof=40, align=8
+// CHECK-X64-NEXT: 16 | struct B0 (virtual base)
+// CHECK-X64-NEXT: 16 | int a
+// CHECK-X64-NEXT: 20 | struct B1 (virtual base)
+// CHECK-X64-NEXT: 20 | int a
+// CHECK-X64-NEXT: | [sizeof=24, align=8
// CHECK-X64-NEXT: | nvsize=16, nvalign=8]
int a[
diff --git a/test/Layout/ms-x86-pack-and-align.cpp b/test/Layout/ms-x86-pack-and-align.cpp
index 0843b3e0bfe409002b68e32ebdb408841311d07f..be0499c2cbbeb210db446c3d68c2f3c950d8b327 100644
--- a/test/Layout/ms-x86-pack-and-align.cpp
+++ b/test/Layout/ms-x86-pack-and-align.cpp
@@ -473,7 +473,7 @@ struct RE {
// CHECK-NEXT: 0 | struct RB2
// CHECK-NEXT: 0 | (RB2 vbtable pointer)
// CHECK-NEXT: 1024 | int b
-// CHECK-NEXT: 1032 | struct RA (virtual base) (empty)
+// CHECK-NEXT: 1028 | struct RA (virtual base) (empty)
// CHECK-NEXT: | [sizeof=1032, align=1024
// CHECK-NEXT: | nvsize=1028, nvalign=1024]
// CHECK: *** Dumping AST Record Layout
@@ -481,7 +481,7 @@ struct RE {
// CHECK-NEXT: 0 | (RB3 vftable pointer)
// CHECK-NEXT: 1024 | (RB3 vbtable pointer)
// CHECK-NEXT: 2048 | int b
-// CHECK-NEXT: 2056 | struct RA (virtual base) (empty)
+// CHECK-NEXT: 2052 | struct RA (virtual base) (empty)
// CHECK-NEXT: | [sizeof=2056, align=1024
// CHECK-NEXT: | nvsize=2052, nvalign=1024]
// CHECK: *** Dumping AST Record Layout
@@ -516,7 +516,7 @@ struct RE {
// CHECK-X64-NEXT: 0 | struct RB2
// CHECK-X64-NEXT: 0 | (RB2 vbtable pointer)
// CHECK-X64-NEXT: 1024 | int b
-// CHECK-X64-NEXT: 1032 | struct RA (virtual base) (empty)
+// CHECK-X64-NEXT: 1028 | struct RA (virtual base) (empty)
// CHECK-X64-NEXT: | [sizeof=1032, align=1024
// CHECK-X64-NEXT: | nvsize=1028, nvalign=1024]
// CHECK-X64: *** Dumping AST Record Layout
@@ -524,7 +524,7 @@ struct RE {
// CHECK-X64-NEXT: 0 | (RB3 vftable pointer)
// CHECK-X64-NEXT: 1024 | (RB3 vbtable pointer)
// CHECK-X64-NEXT: 2048 | int b
-// CHECK-X64-NEXT: 2056 | struct RA (virtual base) (empty)
+// CHECK-X64-NEXT: 2052 | struct RA (virtual base) (empty)
// CHECK-X64-NEXT: | [sizeof=2056, align=1024
// CHECK-X64-NEXT: | nvsize=2052, nvalign=1024]
// CHECK-X64: *** Dumping AST Record Layout