diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp
--- a/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp
@@ -1230,13 +1230,17 @@
   StringRef IncludeDir;
   // Be defensive about the contents of Entry.
   if (getVersion() >= 5) {
-    if (Entry.DirIdx < IncludeDirectories.size())
+    // DirIdx 0 is the compilation directory, so don't include it for
+    // relative names.
+    if ((Entry.DirIdx != 0 || Kind != FileLineInfoKind::RelativeFilePath) &&
+        Entry.DirIdx < IncludeDirectories.size())
       IncludeDir = IncludeDirectories[Entry.DirIdx].getAsCString().getValue();
   } else {
     if (0 < Entry.DirIdx && Entry.DirIdx <= IncludeDirectories.size())
       IncludeDir =
           IncludeDirectories[Entry.DirIdx - 1].getAsCString().getValue();
   }
+
   // For absolute paths only, include the compilation directory of compile unit.
   // We know that FileName is not absolute, the only way to have an absolute
   // path at this point would be if IncludeDir is absolute.
diff --git a/llvm/test/tools/llvm-symbolizer/relativenames.s b/llvm/test/tools/llvm-symbolizer/relativenames.s
--- a/llvm/test/tools/llvm-symbolizer/relativenames.s
+++ b/llvm/test/tools/llvm-symbolizer/relativenames.s
@@ -1,18 +1,108 @@
 # REQUIRES: x86-registered-target
 
-foo:
-    nop
+## Test that the relative names option to llvm-symbolizer works properly.
+## See llvm/docs/CommandGuide/llvm-symbolizer.rst for commands
+## that would produce this test case
 
-# RUN: llvm-mc --filetype=obj --triple=x86_64-pc-linux %s -o %t.o -g
+# RUN: llvm-mc %s -filetype obj -triple x86_64-pc-linux -o %t.o
 
 # RUN: llvm-symbolizer 0 --relativenames --obj=%t.o \
 # RUN:    | FileCheck %s -DDIR=%p --check-prefix=RELATIVENAMES
 
+## Sanity check for default.
+# RUN: llvm-symbolizer 0 --obj=%t.o \
+# RUN:    | FileCheck %s -DDIR=%p --check-prefix=ABSOLUTENAMES
+
 ## Ensure last option wins.
 # RUN: llvm-symbolizer 0 --basenames --relativenames --obj=%t.o \
 # RUN:    | FileCheck %s -DDIR=%p --check-prefix=RELATIVENAMES
 # RUN: llvm-symbolizer 0 --relativenames --basenames --obj=%t.o \
 # RUN:    | FileCheck %s --check-prefix=BASENAMES
 
-# RELATIVENAMES: [[DIR]]{{\\|/}}relativenames.s:4
+# ABSOLUTENAMES: {{\\|/}}tmp{{\\|/}}foo{{\\|/}}relativenames.s:4
+# RELATIVENAMES: {{^}}foo{{\\|/}}relativenames.s:4
 # BASENAMES: {{^}}relativenames.s:4
+
+##  Provide just enough info in debug info for the symbolizer
+##  to find the line table.
+.section .debug_abbrev,"",@progbits
+    .byte 0x01  ## Abbreviation Code
+    .byte 0x11  ## DW_TAG_compile_unit
+    .byte 0x01  ## DW_CHILDREN_yes
+    .byte 0x10  ## DW_AT_stmt_list
+    .byte 0x17  ## DW_FORM_sec_offset
+    .byte 0x11  ## DW_AT_low_pc
+    .byte 0x01  ## DW_FORM_addr
+    .byte 0x12  ## DW_AT_high_pc
+    .byte 0x01  ## DW_FORM_addr
+    .byte 0x1b  ## DW_AT_comp_dir
+    .byte 0x08  ## DW_FORM_string
+    .byte 0x03  ## DW_AT_name
+    .byte 0x08  ## DW_FORM_string
+    .byte 0x00  ## EOM(1)
+    .byte 0x00  ## EOM(2)
+    .byte 0x02  ## Abbreviation Code
+    .byte 0x2e  ## DW_TAG_subprogram
+    .byte 0x0   ## DW_CHILDREN_no
+    .byte 0x11  ## DW_AT_low_pc
+    .byte 0x01  ## DW_FORM_addr
+    .byte 0x12  ## DW_AT_high_pc
+    .byte 0x01  ## DW_FORM_addr
+    .byte 0x00  ## EOM(1)
+    .byte 0x00  ## EOM(2)
+    .byte 0x00  ## EOM(3)
+
+.section .debug_info,"",@progbits
+    .long   .Ldebug_info_end-.Ldebug_info_start ## length
+.Ldebug_info_start:
+    .short 0x05  ## version
+    .byte  0x01  ## DW_TAG_compile_unit
+    .byte  0x08  ## address size
+    .long  .debug_abbrev   ## offset into abbrev section
+    .byte  0x01  ## cu abbrev code
+    .long  .debug_line  ## DW_AT_stmt_list
+    .quad  0x00  ## DW_AT_low_pc
+    .quad  0x01  ## DW_AT_high_pc
+    .asciz "/tmp"  ## DW_AT_comp_dir
+    .asciz "foo/relativenames.s" ## DW_AT_name
+    .byte  0x02  ## subprog abbrev code
+    .quad  0x00  ## DW_AT_low_pc
+    .quad  0x01  ## DW_AT_high_pc
+.Ldebug_info_end:
+
+
+.section .debug_line,"",@progbits
+    .long .Lunit_end - .Lunit_begin ## unit_length
+.Lunit_begin:
+    .short 0x05  ## version
+    .byte  0x08  ## address_size
+    .byte  0x00  ## segment_selector_size
+    .long .Lheader_end - .Lheader_begin ## header_length
+.Lheader_begin:
+    .byte  0x01  ## minimum_instruction_length
+    .byte  0x01  ## maximum_operations_per_instruction
+    .byte  0x01  ## default_is_stmt
+    .byte  0xfb  ## line_base
+    .byte  0x0e  ## line_range
+    .byte  0x0d  ## opcode_base and lengths
+    .byte  0x00, 0x01, 0x01, 0x01, 0x01, 0x00
+    .byte  0x00, 0x00, 0x01, 0x00, 0x00, 0x01
+    .byte  0x01  ## directory entry format count
+    .byte  0x01, 0x8 ## DW_LNCT_path, DW_FORM_string
+    .byte  0x01  ## directories count
+    .asciz "/tmp" ## directory entry 0
+    .byte  0x02  ## file_name_entry_format_count
+    .byte  0x02, 0x0B  ## DW_LNCT_directory_index, DW_FORM_data1
+    .byte  0x01, 0x08  ## DW_LNCT_path, DW_FORM_string
+    .byte  0x01  ## filname count
+    .byte  0x00  ## directory index
+    .asciz "foo/relativenames.s"
+.Lheader_end:
+    .byte 0x04, 0x00 ## set file to zero
+    ## set address to 0x0
+    .byte 0x00, 0x09, 0x02, 0x00, 0x00, 0x00, 0x00
+    .byte 0x00, 0x00, 0x00, 0x00
+    .byte 0x15  ## Advance Address by 0 and line by 3
+    .byte 0x02, 0x01  ## Advance PC by 1
+    .byte 0x0, 0x1, 0x1  ## DW_LNE_end_sequence
+.Lunit_end: