Revert previous patch while I debug the darwin bootstrap failure.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120246 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCMachOStreamer.cpp b/lib/MC/MCMachOStreamer.cpp
index 02a1f08..3f93604 100644
--- a/lib/MC/MCMachOStreamer.cpp
+++ b/lib/MC/MCMachOStreamer.cpp
@@ -105,6 +105,14 @@
 }
 
 void MCMachOStreamer::EmitLabel(MCSymbol *Symbol) {
+  // TODO: This is almost exactly the same as WinCOFFStreamer. Consider merging
+  // into MCObjectStreamer.
+  assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
+  assert(!Symbol->isVariable() && "Cannot emit a variable symbol!");
+  assert(CurSection && "Cannot emit before setting section!");
+
+  Symbol->setSection(*CurSection);
+
   MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
 
   // We have to create a new fragment if this is an atom defining symbol,
@@ -112,7 +120,14 @@
   if (getAssembler().isSymbolLinkerVisible(SD.getSymbol()))
     new MCDataFragment(getCurrentSectionData());
 
-  MCObjectStreamer::EmitLabel(Symbol);
+  // FIXME: This is wasteful, we don't necessarily need to create a data
+  // fragment. Instead, we should mark the symbol as pointing into the data
+  // fragment if it exists, otherwise we should just queue the label and set its
+  // fragment pointer when we emit the next fragment.
+  MCDataFragment *F = getOrCreateDataFragment();
+  assert(!SD.getFragment() && "Unexpected fragment on symbol data!");
+  SD.setFragment(F);
+  SD.setOffset(F->getContents().size());
 
   // This causes the reference type flag to be cleared. Darwin 'as' was "trying"
   // to clear the weak reference and weak definition bits too, but the