libclang: introduce cxstring::createNull()


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@174173 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/libclang/CXComment.cpp b/tools/libclang/CXComment.cpp
index 57bab18..0a90c65 100644
--- a/tools/libclang/CXComment.cpp
+++ b/tools/libclang/CXComment.cpp
@@ -124,7 +124,7 @@
 CXString clang_TextComment_getText(CXComment CXC) {
   const TextComment *TC = getASTNodeAs<TextComment>(CXC);
   if (!TC)
-    return createCXString((const char *) 0);
+    return cxstring::createNull();
 
   return createCXString(TC->getText(), /*DupString=*/ false);
 }
@@ -132,7 +132,7 @@
 CXString clang_InlineCommandComment_getCommandName(CXComment CXC) {
   const InlineCommandComment *ICC = getASTNodeAs<InlineCommandComment>(CXC);
   if (!ICC)
-    return createCXString((const char *) 0);
+    return cxstring::createNull();
 
   const CommandTraits &Traits = getCommandTraits(CXC);
   return createCXString(ICC->getCommandName(Traits), /*DupString=*/ false);
@@ -172,7 +172,7 @@
                                                unsigned ArgIdx) {
   const InlineCommandComment *ICC = getASTNodeAs<InlineCommandComment>(CXC);
   if (!ICC || ArgIdx >= ICC->getNumArgs())
-    return createCXString((const char *) 0);
+    return cxstring::createNull();
 
   return createCXString(ICC->getArgText(ArgIdx), /*DupString=*/ false);
 }
@@ -180,7 +180,7 @@
 CXString clang_HTMLTagComment_getTagName(CXComment CXC) {
   const HTMLTagComment *HTC = getASTNodeAs<HTMLTagComment>(CXC);
   if (!HTC)
-    return createCXString((const char *) 0);
+    return cxstring::createNull();
 
   return createCXString(HTC->getTagName(), /*DupString=*/ false);
 }
@@ -204,7 +204,7 @@
 CXString clang_HTMLStartTag_getAttrName(CXComment CXC, unsigned AttrIdx) {
   const HTMLStartTagComment *HST = getASTNodeAs<HTMLStartTagComment>(CXC);
   if (!HST || AttrIdx >= HST->getNumAttrs())
-    return createCXString((const char *) 0);
+    return cxstring::createNull();
 
   return createCXString(HST->getAttr(AttrIdx).Name, /*DupString=*/ false);
 }
@@ -212,7 +212,7 @@
 CXString clang_HTMLStartTag_getAttrValue(CXComment CXC, unsigned AttrIdx) {
   const HTMLStartTagComment *HST = getASTNodeAs<HTMLStartTagComment>(CXC);
   if (!HST || AttrIdx >= HST->getNumAttrs())
-    return createCXString((const char *) 0);
+    return cxstring::createNull();
 
   return createCXString(HST->getAttr(AttrIdx).Value, /*DupString=*/ false);
 }
@@ -220,7 +220,7 @@
 CXString clang_BlockCommandComment_getCommandName(CXComment CXC) {
   const BlockCommandComment *BCC = getASTNodeAs<BlockCommandComment>(CXC);
   if (!BCC)
-    return createCXString((const char *) 0);
+    return cxstring::createNull();
 
   const CommandTraits &Traits = getCommandTraits(CXC);
   return createCXString(BCC->getCommandName(Traits), /*DupString=*/ false);
@@ -238,7 +238,7 @@
                                               unsigned ArgIdx) {
   const BlockCommandComment *BCC = getASTNodeAs<BlockCommandComment>(CXC);
   if (!BCC || ArgIdx >= BCC->getNumArgs())
-    return createCXString((const char *) 0);
+    return cxstring::createNull();
 
   return createCXString(BCC->getArgText(ArgIdx), /*DupString=*/ false);
 }
@@ -254,7 +254,7 @@
 CXString clang_ParamCommandComment_getParamName(CXComment CXC) {
   const ParamCommandComment *PCC = getASTNodeAs<ParamCommandComment>(CXC);
   if (!PCC || !PCC->hasParamName())
-    return createCXString((const char *) 0);
+    return cxstring::createNull();
 
   return createCXString(PCC->getParamNameAsWritten(), /*DupString=*/ false);
 }
@@ -305,7 +305,7 @@
 CXString clang_TParamCommandComment_getParamName(CXComment CXC) {
   const TParamCommandComment *TPCC = getASTNodeAs<TParamCommandComment>(CXC);
   if (!TPCC || !TPCC->hasParamName())
-    return createCXString((const char *) 0);
+    return cxstring::createNull();
 
   return createCXString(TPCC->getParamNameAsWritten(), /*DupString=*/ false);
 }
@@ -338,7 +338,7 @@
   const VerbatimBlockLineComment *VBL =
       getASTNodeAs<VerbatimBlockLineComment>(CXC);
   if (!VBL)
-    return createCXString((const char *) 0);
+    return cxstring::createNull();
 
   return createCXString(VBL->getText(), /*DupString=*/ false);
 }
@@ -346,7 +346,7 @@
 CXString clang_VerbatimLineComment_getText(CXComment CXC) {
   const VerbatimLineComment *VLC = getASTNodeAs<VerbatimLineComment>(CXC);
   if (!VLC)
-    return createCXString((const char *) 0);
+    return cxstring::createNull();
 
   return createCXString(VLC->getText(), /*DupString=*/ false);
 }
@@ -838,7 +838,7 @@
 CXString clang_HTMLTagComment_getAsString(CXComment CXC) {
   const HTMLTagComment *HTC = getASTNodeAs<HTMLTagComment>(CXC);
   if (!HTC)
-    return createCXString((const char *) 0);
+    return cxstring::createNull();
 
   SmallString<128> HTML;
   CommentASTToHTMLConverter Converter(0, HTML, getCommandTraits(CXC));
@@ -849,7 +849,7 @@
 CXString clang_FullComment_getAsHTML(CXComment CXC) {
   const FullComment *FC = getASTNodeAs<FullComment>(CXC);
   if (!FC)
-    return createCXString((const char *) 0);
+    return cxstring::createNull();
 
   SmallString<1024> HTML;
   CommentASTToHTMLConverter Converter(FC, HTML, getCommandTraits(CXC));
@@ -1377,7 +1377,7 @@
 CXString clang_FullComment_getAsXML(CXComment CXC) {
   const FullComment *FC = getASTNodeAs<FullComment>(CXC);
   if (!FC)
-    return createCXString((const char *) 0);
+    return cxstring::createNull();
   ASTContext &Context = FC->getDeclInfo()->CurrentDecl->getASTContext();
   CXTranslationUnit TU = CXC.TranslationUnit;
   SourceManager &SM = cxtu::getASTUnit(TU)->getSourceManager();