Remove 'using std::errro_code' from lib.

llvm-svn: 210871
diff --git a/llvm/lib/LTO/LTOModule.cpp b/llvm/lib/LTO/LTOModule.cpp
index aee0ef8..eac48e1 100644
--- a/llvm/lib/LTO/LTOModule.cpp
+++ b/llvm/lib/LTO/LTOModule.cpp
@@ -43,7 +43,6 @@
 #include "llvm/Transforms/Utils/GlobalStatus.h"
 #include <system_error>
 using namespace llvm;
-using std::error_code;
 
 LTOModule::LTOModule(llvm::Module *m, llvm::TargetMachine *t)
   : _module(m), _target(t),
@@ -99,7 +98,7 @@
 LTOModule *LTOModule::makeLTOModule(const char *path, TargetOptions options,
                                     std::string &errMsg) {
   std::unique_ptr<MemoryBuffer> buffer;
-  if (error_code ec = MemoryBuffer::getFile(path, buffer)) {
+  if (std::error_code ec = MemoryBuffer::getFile(path, buffer)) {
     errMsg = ec.message();
     return nullptr;
   }
@@ -118,7 +117,7 @@
                                     TargetOptions options,
                                     std::string &errMsg) {
   std::unique_ptr<MemoryBuffer> buffer;
-  if (error_code ec =
+  if (std::error_code ec =
           MemoryBuffer::getOpenFileSlice(fd, path, buffer, map_size, offset)) {
     errMsg = ec.message();
     return nullptr;
@@ -141,7 +140,7 @@
   // parse bitcode buffer
   ErrorOr<Module *> ModuleOrErr =
       getLazyBitcodeModule(buffer, getGlobalContext());
-  if (error_code EC = ModuleOrErr.getError()) {
+  if (std::error_code EC = ModuleOrErr.getError()) {
     errMsg = EC.message();
     delete buffer;
     return nullptr;