diff --git a/lib/MC/ELFObjectWriter.cpp b/lib/MC/ELFObjectWriter.cpp
index b60271f..94251d7 100644
--- a/lib/MC/ELFObjectWriter.cpp
+++ b/lib/MC/ELFObjectWriter.cpp
@@ -274,6 +274,11 @@
     void WriteRelocationsFragment(const MCAssembler &Asm, MCDataFragment *F,
                                   const MCSectionData *SD);
 
+    bool IsFixupFullyResolved(const MCAssembler &Asm,
+                              const MCValue Target,
+                              bool IsPCRel,
+                              const MCFragment *DF) const;
+
     void WriteObject(const MCAssembler &Asm, const MCAsmLayout &Layout);
   };
 
@@ -775,7 +780,7 @@
 
     WriteRelocationsFragment(Asm, F, &SD);
 
-    Asm.AddSectionToTheEnd(RelaSD, Layout);
+    Asm.AddSectionToTheEnd(*Writer, RelaSD, Layout);
   }
 }
 
@@ -873,11 +878,11 @@
   // Symbol table
   F = new MCDataFragment(&SymtabSD);
   WriteSymbolTable(F, Asm, Layout, NumRegularSections);
-  Asm.AddSectionToTheEnd(SymtabSD, Layout);
+  Asm.AddSectionToTheEnd(*Writer, SymtabSD, Layout);
 
   F = new MCDataFragment(&StrtabSD);
   F->getContents().append(StringTable.begin(), StringTable.end());
-  Asm.AddSectionToTheEnd(StrtabSD, Layout);
+  Asm.AddSectionToTheEnd(*Writer, StrtabSD, Layout);
 
   F = new MCDataFragment(&ShstrtabSD);
 
@@ -903,7 +908,41 @@
     F->getContents() += '\x00';
   }
 
-  Asm.AddSectionToTheEnd(ShstrtabSD, Layout);
+  Asm.AddSectionToTheEnd(*Writer, ShstrtabSD, Layout);
+}
+
+bool ELFObjectWriterImpl::IsFixupFullyResolved(const MCAssembler &Asm,
+                                               const MCValue Target,
+                                               bool IsPCRel,
+                                               const MCFragment *DF) const {
+  // If this is a PCrel relocation, find the section this fixup value is
+  // relative to.
+  const MCSection *BaseSection = 0;
+  if (IsPCRel) {
+    BaseSection = &DF->getParent()->getSection();
+    assert(BaseSection);
+  }
+
+  const MCSection *SectionA = 0;
+  const MCSymbol *SymbolA = 0;
+  if (const MCSymbolRefExpr *A = Target.getSymA()) {
+    SymbolA = &A->getSymbol();
+    SectionA = &SymbolA->getSection();
+  }
+
+  const MCSection *SectionB = 0;
+  if (const MCSymbolRefExpr *B = Target.getSymB()) {
+    SectionB = &B->getSymbol().getSection();
+  }
+
+  if (!BaseSection)
+    return SectionA == SectionB;
+
+  const MCSymbolData &DataA = Asm.getSymbolData(*SymbolA);
+  if (DataA.isExternal())
+    return false;
+
+  return !SectionB && BaseSection == SectionA;
 }
 
 void ELFObjectWriterImpl::WriteObject(const MCAssembler &Asm,
@@ -1064,6 +1103,14 @@
                                                   Target, FixedValue);
 }
 
+bool ELFObjectWriter::IsFixupFullyResolved(const MCAssembler &Asm,
+                                           const MCValue Target,
+                                           bool IsPCRel,
+                                           const MCFragment *DF) const {
+  return ((ELFObjectWriterImpl*) Impl)->IsFixupFullyResolved(Asm, Target,
+                                                             IsPCRel, DF);
+}
+
 void ELFObjectWriter::WriteObject(const MCAssembler &Asm,
                                   const MCAsmLayout &Layout) {
   ((ELFObjectWriterImpl*) Impl)->WriteObject(Asm, Layout);
diff --git a/lib/MC/MCAssembler.cpp b/lib/MC/MCAssembler.cpp
index 506f2a6..3d9dcba 100644
--- a/lib/MC/MCAssembler.cpp
+++ b/lib/MC/MCAssembler.cpp
@@ -232,89 +232,6 @@
 MCAssembler::~MCAssembler() {
 }
 
-static bool isScatteredFixupFullyResolvedSimple(const MCAssembler &Asm,
-                                                const MCFixup &Fixup,
-                                                const MCValue Target,
-                                                const MCSection *BaseSection) {
-  // The effective fixup address is
-  //     addr(atom(A)) + offset(A)
-  //   - addr(atom(B)) - offset(B)
-  //   - addr(<base symbol>) + <fixup offset from base symbol>
-  // and the offsets are not relocatable, so the fixup is fully resolved when
-  //  addr(atom(A)) - addr(atom(B)) - addr(<base symbol>)) == 0.
-  //
-  // The simple (Darwin, except on x86_64) way of dealing with this was to
-  // assume that any reference to a temporary symbol *must* be a temporary
-  // symbol in the same atom, unless the sections differ. Therefore, any PCrel
-  // relocation to a temporary symbol (in the same section) is fully
-  // resolved. This also works in conjunction with absolutized .set, which
-  // requires the compiler to use .set to absolutize the differences between
-  // symbols which the compiler knows to be assembly time constants, so we don't
-  // need to worry about considering symbol differences fully resolved.
-
-  // Non-relative fixups are only resolved if constant.
-  if (!BaseSection)
-    return Target.isAbsolute();
-
-  // Otherwise, relative fixups are only resolved if not a difference and the
-  // target is a temporary in the same section.
-  if (Target.isAbsolute() || Target.getSymB())
-    return false;
-
-  const MCSymbol *A = &Target.getSymA()->getSymbol();
-  if (!A->isTemporary() || !A->isInSection() ||
-      &A->getSection() != BaseSection)
-    return false;
-
-  return true;
-}
-
-static bool isScatteredFixupFullyResolved(const MCAssembler &Asm,
-                                          const MCAsmLayout &Layout,
-                                          const MCFixup &Fixup,
-                                          const MCValue Target,
-                                          const MCSymbolData *BaseSymbol) {
-  // The effective fixup address is
-  //     addr(atom(A)) + offset(A)
-  //   - addr(atom(B)) - offset(B)
-  //   - addr(BaseSymbol) + <fixup offset from base symbol>
-  // and the offsets are not relocatable, so the fixup is fully resolved when
-  //  addr(atom(A)) - addr(atom(B)) - addr(BaseSymbol) == 0.
-  //
-  // Note that "false" is almost always conservatively correct (it means we emit
-  // a relocation which is unnecessary), except when it would force us to emit a
-  // relocation which the target cannot encode.
-
-  const MCSymbolData *A_Base = 0, *B_Base = 0;
-  if (const MCSymbolRefExpr *A = Target.getSymA()) {
-    // Modified symbol references cannot be resolved.
-    if (A->getKind() != MCSymbolRefExpr::VK_None)
-      return false;
-
-    A_Base = Asm.getAtom(&Asm.getSymbolData(A->getSymbol()));
-    if (!A_Base)
-      return false;
-  }
-
-  if (const MCSymbolRefExpr *B = Target.getSymB()) {
-    // Modified symbol references cannot be resolved.
-    if (B->getKind() != MCSymbolRefExpr::VK_None)
-      return false;
-
-    B_Base = Asm.getAtom(&Asm.getSymbolData(B->getSymbol()));
-    if (!B_Base)
-      return false;
-  }
-
-  // If there is no base, A and B have to be the same atom for this fixup to be
-  // fully resolved.
-  if (!BaseSymbol)
-    return A_Base == B_Base;
-
-  // Otherwise, B must be missing and A must be the base.
-  return !B_Base && BaseSymbol == A_Base;
-}
-
 bool MCAssembler::isSymbolLinkerVisible(const MCSymbol &Symbol) const {
   // Non-temporary labels should always be visible to the linker.
   if (!Symbol.isTemporary())
@@ -347,7 +264,8 @@
   return SD->getFragment()->getAtom();
 }
 
-bool MCAssembler::EvaluateFixup(const MCAsmLayout &Layout,
+bool MCAssembler::EvaluateFixup(const MCObjectWriter &Writer,
+                                const MCAsmLayout &Layout,
                                 const MCFixup &Fixup, const MCFragment *DF,
                                 MCValue &Target, uint64_t &Value) const {
   ++stats::EvaluateFixup;
@@ -377,31 +295,8 @@
       IsResolved = false;
   }
 
-  // If we are using scattered symbols, determine whether this value is actually
-  // resolved; scattering may cause atoms to move.
-  if (IsResolved && getBackend().hasScatteredSymbols()) {
-    if (getBackend().hasReliableSymbolDifference()) {
-      // If this is a PCrel relocation, find the base atom (identified by its
-      // symbol) that the fixup value is relative to.
-      const MCSymbolData *BaseSymbol = 0;
-      if (IsPCRel) {
-        BaseSymbol = DF->getAtom();
-        if (!BaseSymbol)
-          IsResolved = false;
-      }
-
-      if (IsResolved)
-        IsResolved = isScatteredFixupFullyResolved(*this, Layout, Fixup, Target,
-                                                   BaseSymbol);
-    } else {
-      const MCSection *BaseSection = 0;
-      if (IsPCRel)
-        BaseSection = &DF->getParent()->getSection();
-
-      IsResolved = isScatteredFixupFullyResolvedSimple(*this, Fixup, Target,
-                                                       BaseSection);
-    }
-  }
+  if (IsResolved)
+    IsResolved = Writer.IsFixupFullyResolved(*this, Target, IsPCRel, DF);
 
   if (IsPCRel)
     Value -= Layout.getFragmentAddress(DF) + Fixup.getOffset();
@@ -668,7 +563,8 @@
   assert(OW->getStream().tell() - Start == Layout.getSectionFileSize(SD));
 }
 
-void MCAssembler::AddSectionToTheEnd(MCSectionData &SD, MCAsmLayout &Layout) {
+void MCAssembler::AddSectionToTheEnd(const MCObjectWriter &Writer,
+                                     MCSectionData &SD, MCAsmLayout &Layout) {
   // Create dummy fragments and assign section ordinals.
   unsigned SectionIndex = 0;
   for (MCAssembler::iterator it = begin(), ie = end(); it != ie; ++it)
@@ -697,7 +593,7 @@
   Layout.LayoutSection(&SD);
 
   // Layout until everything fits.
-  while (LayoutOnce(Layout))
+  while (LayoutOnce(Writer, Layout))
     continue;
 
 }
@@ -756,8 +652,17 @@
       it2->setLayoutOrder(FragmentIndex++);
   }
 
+  llvm::OwningPtr<MCObjectWriter> OwnWriter(0);
+  if (Writer == 0) {
+    //no custom Writer_ : create the default one life-managed by OwningPtr
+    OwnWriter.reset(getBackend().createObjectWriter(OS));
+    Writer = OwnWriter.get();
+    if (!Writer)
+      report_fatal_error("unable to create object writer!");
+  }
+
   // Layout until everything fits.
-  while (LayoutOnce(Layout))
+  while (LayoutOnce(*Writer, Layout))
     continue;
 
   DEBUG_WITH_TYPE("mc-dump", {
@@ -773,15 +678,6 @@
 
   uint64_t StartOffset = OS.tell();
 
-  llvm::OwningPtr<MCObjectWriter> OwnWriter(0);
-  if (Writer == 0) {
-    //no custom Writer_ : create the default one life-managed by OwningPtr
-    OwnWriter.reset(getBackend().createObjectWriter(OS));
-    Writer = OwnWriter.get();
-    if (!Writer)
-      report_fatal_error("unable to create object writer!");
-  }
-
   // Allow the object writer a chance to perform post-layout binding (for
   // example, to set the index fields in the symbol data).
   Writer->ExecutePostLayoutBinding(*this);
@@ -801,7 +697,7 @@
         // Evaluate the fixup.
         MCValue Target;
         uint64_t FixedValue;
-        if (!EvaluateFixup(Layout, Fixup, DF, Target, FixedValue)) {
+        if (!EvaluateFixup(*Writer, Layout, Fixup, DF, Target, FixedValue)) {
           // The fixup was unresolved, we need a relocation. Inform the object
           // writer of the relocation, and give it an opportunity to adjust the
           // fixup value if need be.
@@ -819,7 +715,8 @@
   stats::ObjectBytes += OS.tell() - StartOffset;
 }
 
-bool MCAssembler::FixupNeedsRelaxation(const MCFixup &Fixup,
+bool MCAssembler::FixupNeedsRelaxation(const MCObjectWriter &Writer,
+                                       const MCFixup &Fixup,
                                        const MCFragment *DF,
                                        const MCAsmLayout &Layout) const {
   if (getRelaxAll())
@@ -828,7 +725,7 @@
   // If we cannot resolve the fixup value, it requires relaxation.
   MCValue Target;
   uint64_t Value;
-  if (!EvaluateFixup(Layout, Fixup, DF, Target, Value))
+  if (!EvaluateFixup(Writer, Layout, Fixup, DF, Target, Value))
     return true;
 
   // Otherwise, relax if the value is too big for a (signed) i8.
@@ -837,7 +734,8 @@
   return int64_t(Value) != int64_t(int8_t(Value));
 }
 
-bool MCAssembler::FragmentNeedsRelaxation(const MCInstFragment *IF,
+bool MCAssembler::FragmentNeedsRelaxation(const MCObjectWriter &Writer,
+                                          const MCInstFragment *IF,
                                           const MCAsmLayout &Layout) const {
   // If this inst doesn't ever need relaxation, ignore it. This occurs when we
   // are intentionally pushing out inst fragments, or because we relaxed a
@@ -847,13 +745,14 @@
 
   for (MCInstFragment::const_fixup_iterator it = IF->fixup_begin(),
          ie = IF->fixup_end(); it != ie; ++it)
-    if (FixupNeedsRelaxation(*it, IF, Layout))
+    if (FixupNeedsRelaxation(Writer, *it, IF, Layout))
       return true;
 
   return false;
 }
 
-bool MCAssembler::LayoutOnce(MCAsmLayout &Layout) {
+bool MCAssembler::LayoutOnce(const MCObjectWriter &Writer,
+                             MCAsmLayout &Layout) {
   ++stats::RelaxationSteps;
 
   // Layout the sections in order.
@@ -868,7 +767,7 @@
            ie2 = SD.end(); it2 != ie2; ++it2) {
       // Check if this is an instruction fragment that needs relaxation.
       MCInstFragment *IF = dyn_cast<MCInstFragment>(it2);
-      if (!IF || !FragmentNeedsRelaxation(IF, Layout))
+      if (!IF || !FragmentNeedsRelaxation(Writer, IF, Layout))
         continue;
 
       ++stats::RelaxedInstructions;
diff --git a/lib/MC/MachObjectWriter.cpp b/lib/MC/MachObjectWriter.cpp
index f81862e..02a5575 100644
--- a/lib/MC/MachObjectWriter.cpp
+++ b/lib/MC/MachObjectWriter.cpp
@@ -75,6 +75,86 @@
   return false;
 }
 
+static bool isScatteredFixupFullyResolved(const MCAssembler &Asm,
+                                          const MCValue Target,
+                                          const MCSymbolData *BaseSymbol) {
+  // The effective fixup address is
+  //     addr(atom(A)) + offset(A)
+  //   - addr(atom(B)) - offset(B)
+  //   - addr(BaseSymbol) + <fixup offset from base symbol>
+  // and the offsets are not relocatable, so the fixup is fully resolved when
+  //  addr(atom(A)) - addr(atom(B)) - addr(BaseSymbol) == 0.
+  //
+  // Note that "false" is almost always conservatively correct (it means we emit
+  // a relocation which is unnecessary), except when it would force us to emit a
+  // relocation which the target cannot encode.
+
+  const MCSymbolData *A_Base = 0, *B_Base = 0;
+  if (const MCSymbolRefExpr *A = Target.getSymA()) {
+    // Modified symbol references cannot be resolved.
+    if (A->getKind() != MCSymbolRefExpr::VK_None)
+      return false;
+
+    A_Base = Asm.getAtom(&Asm.getSymbolData(A->getSymbol()));
+    if (!A_Base)
+      return false;
+  }
+
+  if (const MCSymbolRefExpr *B = Target.getSymB()) {
+    // Modified symbol references cannot be resolved.
+    if (B->getKind() != MCSymbolRefExpr::VK_None)
+      return false;
+
+    B_Base = Asm.getAtom(&Asm.getSymbolData(B->getSymbol()));
+    if (!B_Base)
+      return false;
+  }
+
+  // If there is no base, A and B have to be the same atom for this fixup to be
+  // fully resolved.
+  if (!BaseSymbol)
+    return A_Base == B_Base;
+
+  // Otherwise, B must be missing and A must be the base.
+  return !B_Base && BaseSymbol == A_Base;
+}
+
+static bool isScatteredFixupFullyResolvedSimple(const MCAssembler &Asm,
+                                                const MCValue Target,
+                                                const MCSection *BaseSection) {
+  // The effective fixup address is
+  //     addr(atom(A)) + offset(A)
+  //   - addr(atom(B)) - offset(B)
+  //   - addr(<base symbol>) + <fixup offset from base symbol>
+  // and the offsets are not relocatable, so the fixup is fully resolved when
+  //  addr(atom(A)) - addr(atom(B)) - addr(<base symbol>)) == 0.
+  //
+  // The simple (Darwin, except on x86_64) way of dealing with this was to
+  // assume that any reference to a temporary symbol *must* be a temporary
+  // symbol in the same atom, unless the sections differ. Therefore, any PCrel
+  // relocation to a temporary symbol (in the same section) is fully
+  // resolved. This also works in conjunction with absolutized .set, which
+  // requires the compiler to use .set to absolutize the differences between
+  // symbols which the compiler knows to be assembly time constants, so we don't
+  // need to worry about considering symbol differences fully resolved.
+
+  // Non-relative fixups are only resolved if constant.
+  if (!BaseSection)
+    return Target.isAbsolute();
+
+  // Otherwise, relative fixups are only resolved if not a difference and the
+  // target is a temporary in the same section.
+  if (Target.isAbsolute() || Target.getSymB())
+    return false;
+
+  const MCSymbol *A = &Target.getSymA()->getSymbol();
+  if (!A->isTemporary() || !A->isInSection() ||
+      &A->getSection() != BaseSection)
+    return false;
+
+  return true;
+}
+
 namespace {
 
 class MachObjectWriterImpl {
@@ -1038,6 +1118,36 @@
                        UndefinedSymbolData);
   }
 
+
+  bool IsFixupFullyResolved(const MCAssembler &Asm,
+                            const MCValue Target,
+                            bool IsPCRel,
+                            const MCFragment *DF) const {
+    // If we are using scattered symbols, determine whether this value is
+    // actually resolved; scattering may cause atoms to move.
+    if (Asm.getBackend().hasScatteredSymbols()) {
+      if (Asm.getBackend().hasReliableSymbolDifference()) {
+        // If this is a PCrel relocation, find the base atom (identified by its
+        // symbol) that the fixup value is relative to.
+        const MCSymbolData *BaseSymbol = 0;
+        if (IsPCRel) {
+          BaseSymbol = DF->getAtom();
+          if (!BaseSymbol)
+            return false;
+        }
+
+        return isScatteredFixupFullyResolved(Asm, Target, BaseSymbol);
+      } else {
+        const MCSection *BaseSection = 0;
+        if (IsPCRel)
+          BaseSection = &DF->getParent()->getSection();
+
+        return isScatteredFixupFullyResolvedSimple(Asm, Target, BaseSection);
+      }
+    }
+    return true;
+  }
+
   void WriteObject(const MCAssembler &Asm, const MCAsmLayout &Layout) {
     unsigned NumSections = Asm.size();
 
@@ -1224,6 +1334,14 @@
                                                    Target, FixedValue);
 }
 
+bool MachObjectWriter::IsFixupFullyResolved(const MCAssembler &Asm,
+                                           const MCValue Target,
+                                           bool IsPCRel,
+                                           const MCFragment *DF) const {
+  return ((MachObjectWriterImpl*) Impl)->IsFixupFullyResolved(Asm, Target,
+                                                              IsPCRel, DF);
+}
+
 void MachObjectWriter::WriteObject(const MCAssembler &Asm,
                                    const MCAsmLayout &Layout) {
   ((MachObjectWriterImpl*) Impl)->WriteObject(Asm, Layout);
diff --git a/lib/MC/WinCOFFObjectWriter.cpp b/lib/MC/WinCOFFObjectWriter.cpp
index 6bebe46..1cc5c09 100644
--- a/lib/MC/WinCOFFObjectWriter.cpp
+++ b/lib/MC/WinCOFFObjectWriter.cpp
@@ -181,6 +181,11 @@
                         MCValue Target,
                         uint64_t &FixedValue);
 
+  virtual bool IsFixupFullyResolved(const MCAssembler &Asm,
+                                    const MCValue Target,
+                                    bool IsPCRel,
+                                    const MCFragment *DF) const;
+
   void WriteObject(const MCAssembler &Asm, const MCAsmLayout &Layout);
 };
 }
@@ -690,6 +695,13 @@
   coff_section->Relocations.push_back(Reloc);
 }
 
+bool WinCOFFObjectWriter::IsFixupFullyResolved(const MCAssembler &Asm,
+                                               const MCValue Target,
+                                               bool IsPCRel,
+                                               const MCFragment *DF) const {
+  return false;
+}
+
 void WinCOFFObjectWriter::WriteObject(const MCAssembler &Asm,
                                       const MCAsmLayout &Layout) {
   // Assign symbol and section indexes and offsets.