Eliminate unnecessary empty string literals.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110183 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGPrinter.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGPrinter.cpp
index 6cae804..8313de5 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGPrinter.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGPrinter.cpp
@@ -199,7 +199,7 @@
 #else
   errs() << "SelectionDAG::getGraphAttrs is only available in debug builds"
          << " on systems with Graphviz or gv!\n";
-  return std::string("");
+  return std::string();
 #endif
 }
 
diff --git a/lib/System/Unix/Path.inc b/lib/System/Unix/Path.inc
index bc104a3..3d88311 100644
--- a/lib/System/Unix/Path.inc
+++ b/lib/System/Unix/Path.inc
@@ -276,7 +276,7 @@
   char pathname[MAXPATHLEN];
   if (!getcwd(pathname,MAXPATHLEN)) {
     assert (false && "Could not query current working directory.");
-    return Path("");
+    return Path();
   }
 
   return Path(pathname);
@@ -408,7 +408,7 @@
 
   std::string::size_type dot = path.rfind('.');
   if (dot == std::string::npos || dot < slash)
-    return StringRef("");
+    return StringRef();
   else
     return StringRef(path).substr(dot + 1);
 }
diff --git a/lib/VMCore/Module.cpp b/lib/VMCore/Module.cpp
index 507d249..d7ddf96 100644
--- a/lib/VMCore/Module.cpp
+++ b/lib/VMCore/Module.cpp
@@ -58,7 +58,7 @@
 //
 
 Module::Module(StringRef MID, LLVMContext& C)
-  : Context(C), Materializer(NULL), ModuleID(MID), DataLayout("")  {
+  : Context(C), Materializer(NULL), ModuleID(MID) {
   ValSymTab = new ValueSymbolTable();
   TypeSymTab = new TypeSymbolTable();
   NamedMDSymTab = new StringMap<NamedMDNode *>();