diff --git a/include/llvm/MC/MCMachObjectWriter.h b/include/llvm/MC/MCMachObjectWriter.h
index 8c67d257a30..6dfa3225d8e 100644
--- a/include/llvm/MC/MCMachObjectWriter.h
+++ b/include/llvm/MC/MCMachObjectWriter.h
@@ -19,10 +19,14 @@ class MCMachObjectTargetWriter {
   const unsigned Is64Bit : 1;
   const uint32_t CPUType;
   const uint32_t CPUSubtype;
+  // FIXME: Remove this, we should just always use it once we no longer care
+  // about Darwin 'as' compatibility.
+  const unsigned UseAggressiveSymbolFolding : 1;
 
 protected:
   MCMachObjectTargetWriter(bool Is64Bit_, uint32_t CPUType_,
-                           uint32_t CPUSubtype_);
+                           uint32_t CPUSubtype_,
+                           bool UseAggressiveSymbolFolding_ = false);
 
 public:
   virtual ~MCMachObjectTargetWriter();
@@ -31,6 +35,7 @@ public:
   /// @{
 
   bool is64Bit() const { return Is64Bit; }
+  bool useAggressiveSymbolFolding() const { return UseAggressiveSymbolFolding; }
   uint32_t getCPUType() const { return CPUType; }
   uint32_t getCPUSubtype() const { return CPUSubtype; }
 
diff --git a/lib/MC/MCMachObjectTargetWriter.cpp b/lib/MC/MCMachObjectTargetWriter.cpp
index 4dfc0a815f3..146cebf01a3 100644
--- a/lib/MC/MCMachObjectTargetWriter.cpp
+++ b/lib/MC/MCMachObjectTargetWriter.cpp
@@ -12,8 +12,10 @@
 using namespace llvm;
 
 MCMachObjectTargetWriter::MCMachObjectTargetWriter(
-  bool Is64Bit_, uint32_t CPUType_, uint32_t CPUSubtype_)
-  : Is64Bit(Is64Bit_), CPUType(CPUType_), CPUSubtype(CPUSubtype_) {
+  bool Is64Bit_, uint32_t CPUType_, uint32_t CPUSubtype_,
+  bool UseAggressiveSymbolFolding_)
+  : Is64Bit(Is64Bit_), CPUType(CPUType_), CPUSubtype(CPUSubtype_),
+    UseAggressiveSymbolFolding(UseAggressiveSymbolFolding_) {
 }
 
 MCMachObjectTargetWriter::~MCMachObjectTargetWriter() {
diff --git a/lib/MC/MachObjectWriter.cpp b/lib/MC/MachObjectWriter.cpp
index 17615eef697..6ebc782c8e2 100644
--- a/lib/MC/MachObjectWriter.cpp
+++ b/lib/MC/MachObjectWriter.cpp
@@ -1126,6 +1126,9 @@ public:
   bool IsSymbolRefDifferenceFullyResolved(const MCAssembler &Asm,
                                           const MCSymbolRefExpr *A,
                                           const MCSymbolRefExpr *B) const {
+    if (!TargetObjectWriter->useAggressiveSymbolFolding())
+      return false;
+
     // The effective address is
     //     addr(atom(A)) + offset(A)
     //   - addr(atom(B)) - offset(B)
diff --git a/lib/Target/X86/X86AsmBackend.cpp b/lib/Target/X86/X86AsmBackend.cpp
index 3f58e43ea15..fe894ab7a14 100644
--- a/lib/Target/X86/X86AsmBackend.cpp
+++ b/lib/Target/X86/X86AsmBackend.cpp
@@ -50,7 +50,8 @@ class X86MachObjectWriter : public MCMachObjectTargetWriter {
 public:
   X86MachObjectWriter(bool Is64Bit, uint32_t CPUType,
                       uint32_t CPUSubtype)
-    : MCMachObjectTargetWriter(Is64Bit, CPUType, CPUSubtype) {}
+    : MCMachObjectTargetWriter(Is64Bit, CPUType, CPUSubtype,
+                               /*UseAggressiveSymbolFolding=*/Is64Bit) {}
 };
 
 class X86AsmBackend : public TargetAsmBackend {