Index: lib/CodeGen/AsmPrinter/CodeViewDebug.h
===================================================================
--- lib/CodeGen/AsmPrinter/CodeViewDebug.h
+++ lib/CodeGen/AsmPrinter/CodeViewDebug.h
@@ -190,6 +190,7 @@
 
   codeview::TypeIndex lowerType(const DIType *Ty);
   codeview::TypeIndex lowerTypeAlias(const DIDerivedType *Ty);
+  codeview::TypeIndex lowerTypeArray(const DICompositeType *Ty);
   codeview::TypeIndex lowerTypeBasic(const DIBasicType *Ty);
   codeview::TypeIndex lowerTypePointer(const DIDerivedType *Ty);
   codeview::TypeIndex lowerTypeMemberPointer(const DIDerivedType *Ty);
Index: lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
===================================================================
--- lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
+++ lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
@@ -736,6 +736,8 @@
 TypeIndex CodeViewDebug::lowerType(const DIType *Ty) {
   // Generic dispatch for lowering an unknown type.
   switch (Ty->getTag()) {
+  case dwarf::DW_TAG_array_type:
+    return lowerTypeArray(cast<DICompositeType>(Ty));
   case dwarf::DW_TAG_typedef:
     return lowerTypeAlias(cast<DIDerivedType>(Ty));
   case dwarf::DW_TAG_base_type:
@@ -775,6 +777,18 @@
   return UnderlyingTypeIndex;
 }
 
+TypeIndex CodeViewDebug::lowerTypeArray(const DICompositeType *Ty) {
+  DITypeRef ElementTypeRef = Ty->getBaseType();
+  TypeIndex ElementTypeIndex = getTypeIndex(ElementTypeRef);
+  // IndexType is size_t, which depends on the bitness of the target.
+  TypeIndex IndexType = Asm->MAI->getPointerSize() == 8 ?
+      TypeIndex(SimpleTypeKind::UInt64Quad) :
+      TypeIndex(SimpleTypeKind::UInt32Long);
+  uint64_t Size = Ty->getSizeInBits() / 8;
+  ArrayRecord Record(ElementTypeIndex, IndexType, Size, Ty->getName());
+  return TypeTable.writeArray(Record);
+}
+
 TypeIndex CodeViewDebug::lowerTypeBasic(const DIBasicType *Ty) {
   TypeIndex Index;
   dwarf::TypeKind Kind;
Index: test/DebugInfo/COFF/types-array.ll
===================================================================
--- /dev/null
+++ test/DebugInfo/COFF/types-array.ll
@@ -0,0 +1,198 @@
+; RUN: llc < %s -filetype=obj | llvm-readobj - -codeview | FileCheck %s
+
+; C++ source to regenerate:
+; $ cat t.cpp
+; void usevars(int, ...);
+; void f() {
+;   int a[5] = {9, 4, 5, 4, 2};
+;   usevars(a[0], a);
+; }
+; $ clang t.cpp -S -emit-llvm -g -gcodeview -o t.ll
+
+; CHECK: CodeViewTypes [
+; CHECK:   Section: .debug$T (6)
+; CHECK:   Magic: 0x4
+; CHECK:   ArgList (0x1000) {
+; CHECK:     TypeLeafKind: LF_ARGLIST (0x1201)
+; CHECK:     NumArgs: 0
+; CHECK:     Arguments [
+; CHECK:     ]
+; CHECK:   }
+; CHECK:   Procedure (0x1001) {
+; CHECK:     TypeLeafKind: LF_PROCEDURE (0x1008)
+; CHECK:     ReturnType: void (0x3)
+; CHECK:     CallingConvention: NearC (0x0)
+; CHECK:     FunctionOptions [ (0x0)
+; CHECK:     ]
+; CHECK:     NumParameters: 0
+; CHECK:     ArgListType: () (0x1000)
+; CHECK:   }
+; CHECK:   FuncId (0x1002) {
+; CHECK:     TypeLeafKind: LF_FUNC_ID (0x1601)
+; CHECK:     ParentScope: 0x0
+; CHECK:     FunctionType: void () (0x1001)
+; CHECK:     Name: f
+; CHECK:   }
+; CHECK:   Array (0x1003) {
+; CHECK:     TypeLeafKind: LF_ARRAY (0x1503)
+; CHECK:     ElementType: int (0x74)
+; CHECK:     IndexType: unsigned long (0x22)
+; CHECK:     SizeOf: 20
+; CHECK:     Name:
+; CHECK:   }
+; CHECK: ]
+; CHECK: CodeViewDebugInfo [
+; CHECK:   Section: .debug$S (5)
+; CHECK:   Magic: 0x4
+; CHECK:   Subsection [
+; CHECK:     SubSectionType: Symbols (0xF1)
+; CHECK:     SubSectionSize: 0x4D
+; CHECK:     ProcStart {
+; CHECK:       PtrParent: 0x0
+; CHECK:       PtrEnd: 0x0
+; CHECK:       PtrNext: 0x0
+; CHECK:       CodeSize: 0x39
+; CHECK:       DbgStart: 0x0
+; CHECK:       DbgEnd: 0x0
+; CHECK:       FunctionType: f (0x1002)
+; CHECK:       CodeOffset: ?f@@YAXXZ+0x0
+; CHECK:       Segment: 0x0
+; CHECK:       Flags [ (0x0)
+; CHECK:       ]
+; CHECK:       DisplayName: f
+; CHECK:       LinkageName: ?f@@YAXXZ
+; CHECK:     }
+; CHECK:     Local {
+; CHECK:       Type: 0x1003
+; CHECK:       Flags [ (0x0)
+; CHECK:       ]
+; CHECK:       VarName: a
+; CHECK:     }
+; CHECK:     DefRangeRegisterRel {
+; CHECK:       BaseRegister: 22
+; CHECK:       HasSpilledUDTMember: No
+; CHECK:       OffsetInParent: 0
+; CHECK:       BasePointerOffset: -20
+; CHECK:       LocalVariableAddrRange {
+; CHECK:         OffsetStart: .text+0x3
+; CHECK:         ISectStart: 0x0
+; CHECK:         Range: 0x36
+; CHECK:       }
+; CHECK:     }
+; CHECK:     ProcEnd {
+; CHECK:     }
+; CHECK:   ]
+; CHECK:   Subsection [
+; CHECK:     SubSectionType: Lines (0xF2)
+; CHECK:     SubSectionSize: 0x48
+; CHECK:     LinkageName: ?f@@YAXXZ
+; CHECK:   ]
+; CHECK:   Subsection [
+; CHECK:     SubSectionType: FileChecksums (0xF4)
+; CHECK:     SubSectionSize: 0x8
+; CHECK:     FileChecksum {
+; CHECK:       Filename: D:\src\llvm\llvm\test\DebugInfo\COFF\t.cpp (0x1)
+; CHECK:       ChecksumSize: 0x0
+; CHECK:       ChecksumKind: None (0x0)
+; CHECK:       ChecksumBytes: ()
+; CHECK:     }
+; CHECK:   ]
+; CHECK:   Subsection [
+; CHECK:     SubSectionType: StringTable (0xF3)
+; CHECK:     SubSectionSize: 0x2C
+; CHECK:   ]
+; CHECK:   FunctionLineTable [
+; CHECK:     LinkageName: ?f@@YAXXZ
+; CHECK:     Flags: 0x1
+; CHECK:     CodeSize: 0x39
+; CHECK:     FilenameSegment [
+; CHECK:       Filename: D:\src\llvm\llvm\test\DebugInfo\COFF\t.cpp (0x0)
+; CHECK:       +0x0 [
+; CHECK:         LineNumberStart: 2
+; CHECK:         LineNumberEndDelta: 0
+; CHECK:         IsStatement: No
+; CHECK:         ColStart: 0
+; CHECK:         ColEnd: 0
+; CHECK:       ]
+; CHECK:       +0x6 [
+; CHECK:         LineNumberStart: 3
+; CHECK:         LineNumberEndDelta: 0
+; CHECK:         IsStatement: No
+; CHECK:         ColStart: 7
+; CHECK:         ColEnd: 0
+; CHECK:       ]
+; CHECK:       +0x2B [
+; CHECK:         LineNumberStart: 4
+; CHECK:         LineNumberEndDelta: 0
+; CHECK:         IsStatement: No
+; CHECK:         ColStart: 3
+; CHECK:         ColEnd: 0
+; CHECK:       ]
+; CHECK:       +0x34 [
+; CHECK:         LineNumberStart: 5
+; CHECK:         LineNumberEndDelta: 0
+; CHECK:         IsStatement: No
+; CHECK:         ColStart: 1
+; CHECK:         ColEnd: 0
+; CHECK:       ]
+; CHECK:     ]
+; CHECK:   ]
+; CHECK: ]
+
+; ModuleID = 't.cpp'
+source_filename = "t.cpp"
+target datalayout = "e-m:x-p:32:32-i64:64-f80:32-n8:16:32-a:0:32-S32"
+target triple = "i686-pc-windows-msvc19.0.23918"
+
+@"\01?a@?1??f@@YAXXZ@3PAHA" = private unnamed_addr constant [5 x i32] [i32 9, i32 4, i32 5, i32 4, i32 2], align 4
+
+define void @"\01?f@@YAXXZ"() #0 !dbg !6 {
+entry:
+  %a = alloca [5 x i32], align 4
+  call void @llvm.dbg.declare(metadata [5 x i32]* %a, metadata !9, metadata !14), !dbg !15
+  %0 = bitcast [5 x i32]* %a to i8*, !dbg !15
+  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %0, i8* bitcast ([5 x i32]* @"\01?a@?1??f@@YAXXZ@3PAHA" to i8*), i32 20, i32 4, i1 false), !dbg !15
+  %arraydecay = getelementptr inbounds [5 x i32], [5 x i32]* %a, i32 0, i32 0, !dbg !16
+  %arrayidx = getelementptr inbounds [5 x i32], [5 x i32]* %a, i32 0, i32 0, !dbg !17
+  %1 = load i32, i32* %arrayidx, align 4, !dbg !17
+  call void (i32, ...) @"\01?usevars@@YAXHZZ"(i32 %1, i32* %arraydecay), !dbg !18
+  ret void, !dbg !19
+}
+
+; Function Attrs: nounwind readnone
+declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
+
+; Function Attrs: argmemonly nounwind
+declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture, i8* nocapture readonly, i32, i32, i1) #2
+
+declare void @"\01?usevars@@YAXHZZ"(i32, ...) #3
+
+attributes #0 = { "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="pentium4" "target-features"="+fxsr,+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { nounwind readnone }
+attributes #2 = { argmemonly nounwind }
+attributes #3 = { "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="pentium4" "target-features"="+fxsr,+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4}
+!llvm.ident = !{!5}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 3.9.0 ", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
+!1 = !DIFile(filename: "t.cpp", directory: "D:\5Csrc\5Cllvm\5Cllvm\5Ctest\5CDebugInfo\5CCOFF")
+!2 = !{}
+!3 = !{i32 2, !"CodeView", i32 1}
+!4 = !{i32 2, !"Debug Info Version", i32 3}
+!5 = !{!"clang version 3.9.0 "}
+!6 = distinct !DISubprogram(name: "f", linkageName: "\01?f@@YAXXZ", scope: !1, file: !1, line: 2, type: !7, isLocal: false, isDefinition: true, scopeLine: 2, flags: DIFlagPrototyped, isOptimized: false, unit: !0, variables: !2)
+!7 = !DISubroutineType(types: !8)
+!8 = !{null}
+!9 = !DILocalVariable(name: "a", scope: !6, file: !1, line: 3, type: !10)
+!10 = !DICompositeType(tag: DW_TAG_array_type, baseType: !11, size: 160, align: 32, elements: !12)
+!11 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
+!12 = !{!13}
+!13 = !DISubrange(count: 5)
+!14 = !DIExpression()
+!15 = !DILocation(line: 3, column: 7, scope: !6)
+!16 = !DILocation(line: 4, column: 17, scope: !6)
+!17 = !DILocation(line: 4, column: 11, scope: !6)
+!18 = !DILocation(line: 4, column: 3, scope: !6)
+!19 = !DILocation(line: 5, column: 1, scope: !6)