--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lld/test/ELF/vs-diagnostics-duplicate.s	Thu Feb 13 15:10:13 2020 +0900
@@ -0,0 +1,76 @@
+// REQUIRES: x86
+// RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t1.o
+// RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %S/Inputs/vs-diagnostics-duplicate2.s -o %t2.o
+// RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %S/Inputs/vs-diagnostics-duplicate3.s -o %t3.o
+// RUN: not ld.lld --vs-diagnostics %t1.o %t2.o %t3.o -o %tout 2>&1 | FileCheck %s
+
+// Case 1. Both symbols have full source location.
+// CHECK:      duplicate.s(15): error: duplicate symbol: bar
+// CHECK-NEXT: >>> defined at duplicate.s:15
+// CHECK-NEXT: >>>{{.*}}1.o:(.text+0x{{.+}})
+// CHECK:      duplicate2.s(20): error: duplicate symbol: bar
+// CHECK-NEXT: >>> defined at duplicate2.s:20
+// CHECK-NEXT: >>>{{.*}}2.o:(.text+0x{{.+}})
+
+// Case 2. The source locations are unknown for both symbols.
+// CHECK:      {{.*}}ld.lld{{.*}}: error: duplicate symbol: foo
+// CHECK-NEXT: >>> defined at {{.*}}1.o:(.text+0x{{.+}})
+// CHECK-NEXT: >>> defined at {{.*}}2.o:(.text+0x{{.+}})
+
+// Case 3. For the second definition of `baz` we know only the source file found in a STT_FILE symbol.
+// CHECK:      duplicate.s(30): error: duplicate symbol: baz
+// CHECK-NEXT: >>> defined at duplicate.s:30
+// CHECK-NEXT: >>> {{.*}}1.o:(.text+0x{{.+}})
+// CHECK-NEXT: >>> defined at duplicate3.s
+// CHECK-NEXT: >>>            {{.*}}3.o:(.text+0x{{.+}})
+
+// Check that we prefer using the full path of a source file.
+// CHECK:      /tmp{{/|\\}}duplicate.s(33): error: duplicate symbol: qux
+// CHECK-NEXT: >>> defined at duplicate.s:33 (/tmp{{/|\\}}duplicate.s:33)
+// CHECK-NEXT: >>> {{.*}}1.o:(.text+0x{{.+}})
+// CHECK-NEXT: >>> defined at duplicate3.s
+// CHECK-NEXT: >>>            {{.*}}3.o:(.text+0x{{.+}})
+
+.global _start, foo, bar, baz, qux
+.text
+_start:
+  nop
+
+foo:
+  nop
+
+.file 1 "duplicate.s"
+.loc 1 15
+
+bar:
+  nop
+
+.loc 1 30
+baz:
+  nop
+
+.file 2 "/tmp" "duplicate.s"
+.loc 2 33
+qux:
+  nop
+
+.section .debug_abbrev,"",@progbits
+  .byte  1                      # Abbreviation Code
+  .byte 17                      # DW_TAG_compile_unit
+  .byte  0                      # DW_CHILDREN_no
+  .byte 16                      # DW_AT_stmt_list
+  .byte 23                      # DW_FORM_sec_offset
+  .byte  0                      # EOM(1)
+  .byte  0                      # EOM(2)
+  .byte  0                      # EOM(3)
+
+.section .debug_info,"",@progbits
+  .long .Lend0 - .Lbegin0       # Length of Unit
+.Lbegin0:
+  .short 4                      # DWARF version number
+  .long  .debug_abbrev          # Offset Into Abbrev. Section
+  .byte  8                      # Address Size (in bytes)
+  .byte  1                      # Abbrev [1] 0xb:0x1f DW_TAG_compile_unit
+  .long  .debug_line            # DW_AT_stmt_list
+.Lend0:
+  .section .debug_line,"",@progbits