[C++11] Use 'nullptr'.

llvm-svn: 210447
diff --git a/clang-tools-extra/modularize/ModuleAssistant.cpp b/clang-tools-extra/modularize/ModuleAssistant.cpp
index 384ac1b..ba9912d 100644
--- a/clang-tools-extra/modularize/ModuleAssistant.cpp
+++ b/clang-tools-extra/modularize/ModuleAssistant.cpp
@@ -124,7 +124,7 @@
     if ((*I)->Name == SubName)
       return *I;
   }
-  return 0;
+  return nullptr;
 }
 
 // Implementation functions:
@@ -135,7 +135,7 @@
 static const char *ReservedNames[] = {
   "config_macros", "export",   "module", "conflict", "framework",
   "requires",      "exclude",  "header", "private",  "explicit",
-  "link",          "umbrella", "extern", "use",      0 // Flag end.
+  "link",          "umbrella", "extern", "use",      nullptr // Flag end.
 };
 
 // Convert module name to a non-keyword.
@@ -143,7 +143,7 @@
 static std::string
 ensureNoCollisionWithReservedName(llvm::StringRef MightBeReservedName) {
   std::string SafeName = MightBeReservedName;
-  for (int Index = 0; ReservedNames[Index] != 0; ++Index) {
+  for (int Index = 0; ReservedNames[Index] != nullptr; ++Index) {
     if (MightBeReservedName == ReservedNames[Index]) {
       SafeName.insert(0, "_");
       break;
@@ -190,7 +190,7 @@
     std::string Stem = llvm::sys::path::stem(*I);
     Stem = ensureNoCollisionWithReservedName(Stem);
     Module *SubModule = CurrentModule->findSubModule(Stem);
-    if (SubModule == 0) {
+    if (!SubModule) {
       SubModule = new Module(Stem);
       CurrentModule->SubModules.push_back(SubModule);
     }
@@ -222,7 +222,7 @@
        I != E; ++I) {
     // Add as a module.
     if (!addModuleDescription(RootModule, *I, HeaderPrefix, Dependencies))
-      return NULL;
+      return nullptr;
   }
 
   return RootModule;