diff --git a/lib/MC/MachObjectWriter.cpp b/lib/MC/MachObjectWriter.cpp
index 5c4d6f2375e..c8fe40e2f43 100644
--- a/lib/MC/MachObjectWriter.cpp
+++ b/lib/MC/MachObjectWriter.cpp
@@ -931,6 +931,20 @@ public:
       // Report as 'long', even though that is not quite accurate.
       Log2Size = llvm::Log2_32(4);
       return true;
+
+      // Handle Thumb branches.
+    case ARM::fixup_arm_thumb_br:
+      Log2Size = llvm::Log2_32(2);
+      return true;
+
+    case ARM::fixup_arm_thumb_bl:
+      Log2Size = llvm::Log2_32(4);
+      return true;
+
+    case ARM::fixup_arm_thumb_blx:
+      // Report as 'long', even though that is not quite accurate.
+      Log2Size = llvm::Log2_32(4);
+      return true;
     }
   }
   void RecordARMRelocation(const MCAssembler &Asm, const MCAsmLayout &Layout,
diff --git a/test/MC/MachO/darwin-Thumb-reloc.s b/test/MC/MachO/darwin-Thumb-reloc.s
new file mode 100644
index 00000000000..263a8035581
--- /dev/null
+++ b/test/MC/MachO/darwin-Thumb-reloc.s
@@ -0,0 +1,139 @@
+@ RUN: llvm-mc -n -triple thumbv7-apple-darwin10 %s -filetype=obj -o %t.obj
+@ RUN: macho-dump --dump-section-data < %t.obj > %t.dump
+@ RUN: FileCheck < %t.dump %s
+
+	.syntax unified
+	.section	__TEXT,__text,regular,pure_instructions
+	.globl	_main
+	.align	2
+	.code	16
+	.thumb_func	_main
+_main:
+LPC0_0:
+	blx	_printf
+	.align	2
+LCPI0_0:
+	.long	L_.str-(LPC0_0+4)
+
+	.section	__TEXT,__cstring,cstring_literals
+	.align	2
+L_.str:
+	.asciz	 "s0"
+
+.subsections_via_symbols
+
+@ CHECK: ('cputype', 12)
+@ CHECK: ('cpusubtype', 9)
+@ CHECK: ('filetype', 1)
+@ CHECK: ('num_load_commands', 3)
+@ CHECK: ('load_commands_size', 296)
+@ CHECK: ('flag', 8192)
+@ CHECK: ('load_commands', [
+@ CHECK:   # Load Command 0
+@ CHECK:  (('command', 1)
+@ CHECK:   ('size', 192)
+@ CHECK:   ('segment_name', '\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+@ CHECK:   ('vm_addr', 0)
+@ CHECK:   ('vm_size', 11)
+@ CHECK:   ('file_offset', 324)
+@ CHECK:   ('file_size', 11)
+@ CHECK:   ('maxprot', 7)
+@ CHECK:   ('initprot', 7)
+@ CHECK:   ('num_sections', 2)
+@ CHECK:   ('flags', 0)
+@ CHECK:   ('sections', [
+@ CHECK:     # Section 0
+@ CHECK:    (('section_name', '__text\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+@ CHECK:     ('segment_name', '__TEXT\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+@ CHECK:     ('address', 0)
+@ CHECK:     ('size', 8)
+@ CHECK:     ('offset', 324)
+@ CHECK:     ('alignment', 2)
+@ CHECK:     ('reloc_offset', 336)
+@ CHECK:     ('num_reloc', 3)
+@ CHECK:     ('flags', 0x80000400)
+@ CHECK:     ('reserved1', 0)
+@ CHECK:     ('reserved2', 0)
+@ CHECK:    ),
+@ CHECK:   ('_relocations', [
+@ CHECK:     # Relocation 0
+@ CHECK:     (('word-0', 0xa2000004),
+@ CHECK:      ('word-1', 0x8)),
+@ CHECK:     # Relocation 1
+@ CHECK:     (('word-0', 0xa1000000),
+@ CHECK:      ('word-1', 0x0)),
+@ CHECK:     # Relocation 2
+@ CHECK:     (('word-0', 0x0),
+@ CHECK-FIXME:      ('word-1', 0x6d000001)),
+@ CHECK:   ])
+@ CHECK-FIXME:   ('_section_data', 'fff7feef 04000000')
+@ CHECK:     # Section 1
+@ CHECK:    (('section_name', '__cstring\x00\x00\x00\x00\x00\x00\x00')
+@ CHECK:     ('segment_name', '__TEXT\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+@ CHECK:     ('address', 8)
+@ CHECK:     ('size', 3)
+@ CHECK:     ('offset', 332)
+@ CHECK:     ('alignment', 2)
+@ CHECK:     ('reloc_offset', 0)
+@ CHECK:     ('num_reloc', 0)
+@ CHECK:     ('flags', 0x2)
+@ CHECK:     ('reserved1', 0)
+@ CHECK:     ('reserved2', 0)
+@ CHECK:    ),
+@ CHECK:   ('_relocations', [
+@ CHECK:   ])
+@ CHECK:   ('_section_data', '733000')
+@ CHECK:   ])
+@ CHECK:  ),
+@ CHECK:   # Load Command 1
+@ CHECK:  (('command', 2)
+@ CHECK:   ('size', 24)
+@ CHECK:   ('symoff', 360)
+@ CHECK:   ('nsyms', 2)
+@ CHECK:   ('stroff', 384)
+@ CHECK:   ('strsize', 16)
+@ CHECK:   ('_string_data', '\x00_main\x00_printf\x00\x00')
+@ CHECK:   ('_symbols', [
+@ CHECK:     # Symbol 0
+@ CHECK:    (('n_strx', 1)
+@ CHECK:     ('n_type', 0xf)
+@ CHECK:     ('n_sect', 1)
+@ CHECK-FIXME:     ('n_desc', 8)
+@ CHECK:     ('n_value', 0)
+@ CHECK:     ('_string', '_main')
+@ CHECK:    ),
+@ CHECK:     # Symbol 1
+@ CHECK:    (('n_strx', 7)
+@ CHECK:     ('n_type', 0x1)
+@ CHECK:     ('n_sect', 0)
+@ CHECK:     ('n_desc', 0)
+@ CHECK:     ('n_value', 0)
+@ CHECK:     ('_string', '_printf')
+@ CHECK:    ),
+@ CHECK:   ])
+@ CHECK:  ),
+@ CHECK:   # Load Command 2
+@ CHECK:  (('command', 11)
+@ CHECK:   ('size', 80)
+@ CHECK:   ('ilocalsym', 0)
+@ CHECK:   ('nlocalsym', 0)
+@ CHECK:   ('iextdefsym', 0)
+@ CHECK:   ('nextdefsym', 1)
+@ CHECK:   ('iundefsym', 1)
+@ CHECK:   ('nundefsym', 1)
+@ CHECK:   ('tocoff', 0)
+@ CHECK:   ('ntoc', 0)
+@ CHECK:   ('modtaboff', 0)
+@ CHECK:   ('nmodtab', 0)
+@ CHECK:   ('extrefsymoff', 0)
+@ CHECK:   ('nextrefsyms', 0)
+@ CHECK:   ('indirectsymoff', 0)
+@ CHECK:   ('nindirectsyms', 0)
+@ CHECK:   ('extreloff', 0)
+@ CHECK:   ('nextrel', 0)
+@ CHECK:   ('locreloff', 0)
+@ CHECK:   ('nlocrel', 0)
+@ CHECK:   ('_indirect_symbols', [
+@ CHECK:   ])
+@ CHECK:  ),
+@ CHECK: ])