Index: lib/CodeGen/AsmPrinter/DwarfUnit.cpp
===================================================================
--- lib/CodeGen/AsmPrinter/DwarfUnit.cpp
+++ lib/CodeGen/AsmPrinter/DwarfUnit.cpp
@@ -1404,10 +1404,12 @@
     return IndexTyDie;
   // Construct an integer type to use for indexes.
   IndexTyDie = &createAndAddDIE(dwarf::DW_TAG_base_type, getUnitDie());
-  addString(*IndexTyDie, dwarf::DW_AT_name, "sizetype");
+  StringRef Name = "sizetype";
+  addString(*IndexTyDie, dwarf::DW_AT_name, Name);
   addUInt(*IndexTyDie, dwarf::DW_AT_byte_size, None, sizeof(int64_t));
   addUInt(*IndexTyDie, dwarf::DW_AT_encoding, dwarf::DW_FORM_data1,
           dwarf::DW_ATE_unsigned);
+  DD->addAccelType(Name, *IndexTyDie, /*Flags*/ 0);
   return IndexTyDie;
 }
 
Index: test/DebugInfo/Generic/debug-names-index-type.ll
===================================================================
--- /dev/null
+++ test/DebugInfo/Generic/debug-names-index-type.ll
@@ -0,0 +1,38 @@
+; REQUIRES: object-emission
+; RUN: %llc_dwarf -accel-tables=Dwarf -filetype=obj -o %t < %s
+; RUN: llvm-dwarfdump -debug-names %t | FileCheck %s
+; RUN: llvm-dwarfdump -debug-names -verify %t | FileCheck --check-prefix=VERIFY %s
+
+; Check that the entry for the "sizetype" index type is present in the
+; accelerator table.
+; CHECK: String: 0x{{[0-9a-f]*}} "sizetype"
+; CHECK-NEXT: Entry
+; CHECK-NEXT: Abbrev
+; CHECK-NEXT: Tag: DW_TAG_base_type
+
+; VERIFY: No errors.
+
+; Generated by:
+; clang -g -x c - -o - -S -emit-llvm <<<"int a[1];"
+
+@a = common dso_local global [1 x i32] zeroinitializer, align 4, !dbg !0
+
+!llvm.dbg.cu = !{!2}
+!llvm.module.flags = !{!11, !12, !13}
+!llvm.ident = !{!14}
+
+!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression())
+!1 = distinct !DIGlobalVariable(name: "a", scope: !2, file: !6, line: 1, type: !7, isLocal: false, isDefinition: true)
+!2 = distinct !DICompileUnit(language: DW_LANG_C99, file: !3, producer: "clang version 7.0.0 (trunk 329543) (llvm/trunk 329575)", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !5)
+!3 = !DIFile(filename: "-", directory: "/tmp")
+!4 = !{}
+!5 = !{!0}
+!6 = !DIFile(filename: "<stdin>", directory: "/tmp")
+!7 = !DICompositeType(tag: DW_TAG_array_type, baseType: !8, size: 32, elements: !9)
+!8 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!9 = !{!10}
+!10 = !DISubrange(count: 1)
+!11 = !{i32 2, !"Dwarf Version", i32 4}
+!12 = !{i32 2, !"Debug Info Version", i32 3}
+!13 = !{i32 1, !"wchar_size", i32 4}
+!14 = !{!"clang version 7.0.0 (trunk 329543) (llvm/trunk 329575)"}