Explicit symbols for gnu mimicing relocations. Patch by Jack Carter

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145911 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/ELFObjectWriter.h b/lib/MC/ELFObjectWriter.h
index 7838206..9adf0b1 100644
--- a/lib/MC/ELFObjectWriter.h
+++ b/lib/MC/ELFObjectWriter.h
@@ -445,6 +445,12 @@
     virtual void WriteEFlags();
 
   protected:
+    virtual const MCSymbol *ExplicitRelSym(const MCAssembler &Asm,
+                                           const MCValue &Target,
+                                           const MCFragment &F,
+                                           const MCFixup &Fixup,
+                                           bool IsPCRel) const;
+
     virtual unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup,
                                   bool IsPCRel, bool IsRelocWithSymbol,
                                   int64_t Addend);