Index: lib/Target/AMDGPU/MCTargetDesc/AMDGPUELFObjectWriter.cpp
===================================================================
--- lib/Target/AMDGPU/MCTargetDesc/AMDGPUELFObjectWriter.cpp
+++ lib/Target/AMDGPU/MCTargetDesc/AMDGPUELFObjectWriter.cpp
@@ -30,8 +30,10 @@
 
 } // End anonymous namespace
 
+#define ELFOSABI_AMDGPU_HSA 64
+
 AMDGPUELFObjectWriter::AMDGPUELFObjectWriter(bool Is64Bit)
-  : MCELFObjectTargetWriter(Is64Bit, 0, ELF::EM_AMDGPU, false) { }
+  : MCELFObjectTargetWriter(Is64Bit, ELFOSABI_AMDGPU_HSA, ELF::EM_AMDGPU, false) { }
 
 MCObjectWriter *llvm::createAMDGPUELFObjectWriter(bool Is64Bit, raw_pwrite_stream &OS) {
   MCELFObjectTargetWriter *MOTW = new AMDGPUELFObjectWriter(Is64Bit);
Index: test/CodeGen/AMDGPU/elf.ll
===================================================================
--- test/CodeGen/AMDGPU/elf.ll
+++ test/CodeGen/AMDGPU/elf.ll
@@ -9,6 +9,8 @@
 ; RUN: llc < %s -mtriple=amdgcn-pc-mingw -mcpu=SI -verify-machineinstrs -filetype=obj | llvm-readobj -s -symbols -file-headers - | FileCheck --check-prefix=ELF %s
 
 ; ELF: Format: ELF64
+; 0x40 is machine dependent, but llvm defines it as C600_ELFABI.
+; ELF: OS/ABI: C6000_ELFABI (0x40)
 ; ELF: Machine: EM_AMDGPU (0xE0)
 ; ELF: Name: .AMDGPU.config
 ; ELF: Type: SHT_PROGBITS