Change some methods in MCDwarf.cpp to be able to handle an arbitrary
MCStreamer instead of just MCObjectStreamer. Address changes cannot
be as efficient as we have to use DW_LNE_set_addres, but at least
most of the logic is shared.

This will be used so that, with CodeGen still using EmitDwarfLocDirective,
llvm-gcc is able to produce debug_line sections without needing an
assembler that supports .loc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119777 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/TargetMachine.cpp b/lib/Target/TargetMachine.cpp
index 705b1c0..c4790a2 100644
--- a/lib/Target/TargetMachine.cpp
+++ b/lib/Target/TargetMachine.cpp
@@ -219,7 +219,8 @@
 
 TargetMachine::TargetMachine(const Target &T) 
   : TheTarget(T), AsmInfo(0),
-    MCRelaxAll(false) {
+    MCRelaxAll(false),
+    MCUseLoc(true) {
   // Typically it will be subtargets that will adjust FloatABIType from Default
   // to Soft or Hard.
   if (UseSoftFloat)