--- old/src/hotspot/share/utilities/elfFile.hpp	2018-02-15 12:29:54.163952684 -0500
+++ new/src/hotspot/share/utilities/elfFile.hpp	2018-02-15 12:29:53.974953080 -0500
@@ -45,6 +45,7 @@
 typedef Elf64_Shdr      Elf_Shdr;
 typedef Elf64_Phdr      Elf_Phdr;
 typedef Elf64_Sym       Elf_Sym;
+typedef Elf64_Nhdr      Elf_Nhdr;
 
 #if !defined(_ALLBSD_SOURCE) || defined(__APPLE__)
 #define ELF_ST_TYPE ELF64_ST_TYPE
@@ -61,6 +62,7 @@
 typedef Elf32_Shdr      Elf_Shdr;
 typedef Elf32_Phdr      Elf_Phdr;
 typedef Elf32_Sym       Elf_Sym;
+typedef Elf32_Nhdr      Elf_Nhdr;
 
 #if !defined(_ALLBSD_SOURCE) || defined(__APPLE__)
 #define ELF_ST_TYPE ELF32_ST_TYPE
@@ -117,6 +119,13 @@
   bool has_mark() const { return _marked_pos >= 0; }
 };
 
+// Interface to external debug info file
+class ElfDebugInfo : public CHeapObj<mtInternal> {
+public:
+  virtual bool decode(address addr, char* const buf, size_t buflen, int* offset) = 0;
+  virtual bool has_error() const = 0;
+};
+
 // ElfFile is basically an elf file parser, which can lookup the symbol
 // that is the nearest to the given address.
 // Beware, this code is called from vm error reporting code, when vm is already
@@ -148,10 +157,13 @@
   // function descriptors table
   ElfFuncDescTable* _funcDesc_table;
 
+  // external debug info
+  ElfDebugInfo*     _debuginfo;
+
   NullDecoder::decoder_status  _status;
 
 public:
-  ElfFile(const char* filepath);
+  ElfFile(const char* filepath, bool load_debug_info = true);
   ~ElfFile();
 
   bool decode(address addr, char* buf, int buflen, int* offset);
@@ -182,6 +194,12 @@
   // parse this elf file
   NullDecoder::decoder_status parse_elf(const char* filename);
 
+  // load external debuginfo file for this file.
+  ElfDebugInfo* load_debuginfo() NOT_LINUX({ return NULL; });
+
+  // internal implementation
+  bool decode_impl(address addr, char* buf, int buflen, int* offset);  
+
   // load string, symbol and function descriptor tables from the elf file
   NullDecoder::decoder_status load_tables();