Remove Lexer::BufferStart, an unneeded instance var.

llvm-svn: 38615

clang/Lex/Lexer.cpp

@@ -40,7 +40,6 @@ static void InitCharacterInfo();
 Lexer::Lexer(const SourceBuffer *File, unsigned fileid, Preprocessor &pp,
              const char *BufStart, const char *BufEnd)
   : BufferPtr(BufStart ? BufStart : File->getBufferStart()),
-    BufferStart(BufferPtr),
     BufferEnd(BufEnd ? BufEnd : File->getBufferEnd()),
     InputFile(File), CurFileID(fileid), PP(pp), Features(PP.getLangOptions()) {
   Is_PragmaLexer = false;

clang/Lex/Preprocessor.cpp

@@ -420,7 +420,7 @@ void Preprocessor::EnterSourceFileWithLexer(Lexer *TheLexer,
           SourceMgr.getFileEntryForFileID(CurLexer->getCurFileID()))
       FileType = getFileInfo(FE).DirInfo;
     
-    FileChangeHandler(CurLexer->getSourceLocation(CurLexer->BufferStart),
+    FileChangeHandler(SourceLocation(CurLexer->getCurFileID(), 0),
                       EnterFile, FileType);
   }
 }

clang/include/clang/Lex/Lexer.h

@@ -52,7 +52,6 @@ struct LangOptions {
 /// on the specified Preprocessor object to handle preprocessor directives, etc.
 class Lexer {
   const char *BufferPtr;         // Current pointer into the buffer.
-  const char * const BufferStart;// Start of the buffer.
   const char * const BufferEnd;  // End of the buffer.
   const SourceBuffer *InputFile; // The file we are reading from.
   unsigned CurFileID;            // FileID for the current input file.