_[A-Z] identifiers are reserved for the implementation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108682 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCStreamer.cpp b/lib/MC/MCStreamer.cpp
index 573f2a3..f682721 100644
--- a/lib/MC/MCStreamer.cpp
+++ b/lib/MC/MCStreamer.cpp
@@ -15,7 +15,7 @@
 #include <cstdlib>
 using namespace llvm;
 
-MCStreamer::MCStreamer(MCContext &_Context) : Context(_Context), CurSection(0) {
+MCStreamer::MCStreamer(MCContext &Ctx) : Context(Ctx), CurSection(0) {
 }
 
 MCStreamer::~MCStreamer() {