; Make sure the backend generates a single DIE and uses ref_addr.
; CHECK: 0x[[BASE:.*]]: DW_TAG_structure_type
; CHECK-NEXT: DW_AT_name {{.*}} = "Base"
; CHECK-NOT: DW_TAG_structure_type
; CHECK: 0x[[INT:.*]]: DW_TAG_base_type
; CHECK-NEXT: DW_AT_name {{.*}} = "int"
; CHECK-NOT: DW_TAG_base_type

; CHECK: DW_TAG_compile_unit
; CHECK: DW_TAG_formal_parameter
; CHECK: DW_AT_type [DW_FORM_ref_addr] {{.*}}[[INT]])
; CHECK: DW_TAG_variable
; CHECK: DW_AT_type [DW_FORM_ref_addr] {{.*}}[[BASE]])

; Make sure llvm-link only generates a single copy of the struct.
; LINK: DW_TAG_structure_type
; LINK-NOT: DW_TAG_structure_type

; Content of header files:
; struct Base {
;   int a;
;   Base *b;
; };
; Content of foo.cpp:
; 
; #include "a.hpp"
; void f(int a) {
;   Base t;
; }
; Content of bar.cpp:
; 
; #include "a.hpp"
; void f(int);
; void g(int a) {
;   Base t;
; }
; int main() {
;   f(0);
;   g(1);
;   return 0;
; }
; ModuleID = 'foo.cpp'

%struct.Base = type { i32, %struct.Base* }

; Function Attrs: nounwind ssp uwtable
define void @_Z1fi(i32 %a) #0 {
entry:
  %a.addr = alloca i32, align 4
  %t = alloca %struct.Base, align 8
  store i32 %a, i32* %a.addr, align 4
  call void @llvm.dbg.declare(metadata !{i32* %a.addr}, metadata !17), !dbg !18
  call void @llvm.dbg.declare(metadata !{%struct.Base* %t}, metadata !19), !dbg !20
  ret void, !dbg !21
}

; Function Attrs: nounwind readnone
declare void @llvm.dbg.declare(metadata, metadata) #1

attributes #0 = { nounwind ssp uwtable "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" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #1 = { nounwind readnone }

!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!16, !22}

!0 = metadata !{i32 786449, metadata !1, i32 4, metadata !"clang version 3.4 (http://llvm.org/git/clang.git 8a3f9e46cb988d2c664395b21910091e3730ae82) (http://llvm.org/git/llvm.git 4699e9549358bc77824a59114548eecc3f7c523c)", i1 false, metadata !"", i32 0, metadata !2, metadata !3, metadata !11, metadata !2, metadata !2, metadata !""} ; [ DW_TAG_compile_unit ] [foo.cpp] [DW_LANG_C_plus_plus]
!1 = metadata !{metadata !"foo.cpp", metadata !"."}
!2 = metadata !{i32 0}
!3 = metadata !{metadata !4}
!4 = metadata !{i32 786451, metadata !5, null, metadata !"Base", i32 1, i64 128, i64 64, i32 0, i32 0, null, metadata !6, i32 0, null, null, metadata !"_ZTS4Base"} ; [ DW_TAG_structure_type ] [Base] [line 1, size 128, align 64, offset 0] [def] [from ]
!5 = metadata !{metadata !"./a.hpp", metadata !"."}
!6 = metadata !{metadata !7, metadata !9}
!7 = metadata !{i32 786445, metadata !5, metadata !"_ZTS4Base", metadata !"a", i32 2, i64 32, i64 32, i64 0, i32 0, metadata !8} ; [ DW_TAG_member ] [a] [line 2, size 32, align 32, offset 0] [from int]
!8 = metadata !{i32 786468, null, null, metadata !"int", i32 0, i64 32, i64 32, i64 0, i32 0, i32 5} ; [ DW_TAG_base_type ] [int] [line 0, size 32, align 32, offset 0, enc DW_ATE_signed]
!9 = metadata !{i32 786445, metadata !5, metadata !"_ZTS4Base", metadata !"b", i32 3, i64 64, i64 64, i64 64, i32 0, metadata !10} ; [ DW_TAG_member ] [b] [line 3, size 64, align 64, offset 64] [from ]
!10 = metadata !{i32 786447, null, null, metadata !"", i32 0, i64 64, i64 64, i64 0, i32 0, metadata !"_ZTS4Base"}
!11 = metadata !{metadata !12}
!12 = metadata !{i32 786478, metadata !1, metadata !13, metadata !"f", metadata !"f", metadata !"_Z1fi", i32 3, metadata !14, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 false, void (i32)* @_Z1fi, null, null, metadata !2, i32 3} ; [ DW_TAG_subprogram ] [line 3] [def] [f]
!13 = metadata !{i32 786473, metadata !1}         ; [ DW_TAG_file_type ] [foo.cpp]
!14 = metadata !{i32 786453, i32 0, null, metadata !"", i32 0, i64 0, i64 0, i64 0, i32 0, null, metadata !15, i32 0, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
!15 = metadata !{null, metadata !8}
!16 = metadata !{i32 2, metadata !"Dwarf Version", i32 2}
!17 = metadata !{i32 786689, metadata !12, metadata !"a", metadata !13, i32 16777219, metadata !8, i32 0, i32 0} ; [ DW_TAG_arg_variable ] [a] [line 3]
!18 = metadata !{i32 3, i32 0, metadata !12, null}
!19 = metadata !{i32 786688, metadata !12, metadata !"t", metadata !13, i32 4, metadata !4, i32 0, i32 0} ; [ DW_TAG_auto_variable ] [t] [line 4]
!20 = metadata !{i32 4, i32 0, metadata !12, null}
!21 = metadata !{i32 5, i32 0, metadata !12, null}
!22 = metadata !{i32 1, metadata !"Debug Info Version", i32 1}