Implement scanning-for-( more correctly. This implements

test/Preprocessor/macro_fn_lparen_scan.c, but is not yet complete.

llvm-svn: 38695

clang/include/clang/Lex/MacroExpander.h

@@ -82,6 +82,13 @@ public:
     delete FormalArgs;
   }
   
+  /// NextTokenIsKnownNotLParen - If the next token lexed will pop this macro
+  /// off the expansion stack, return false and set RanOffEnd to true.
+  /// Otherwise, return true if we know for sure that the next token returned
+  /// will not be a '(' token.  Return false if it is a '(' token or if we are
+  /// not sure.
+  bool NextTokenIsKnownNotLParen(bool &RanOffEnd) const;
+  
   MacroInfo &getMacro() const { return Macro; }
 
   /// Lex - Lex and return a token from this macro stream.

clang/include/clang/Lex/Preprocessor.h

@@ -467,6 +467,11 @@ private:
   /// the macro should not be expanded return true, otherwise return false.
   bool HandleMacroExpandedIdentifier(LexerToken &Tok, MacroInfo *MI);
   
+  /// isNextPPTokenLParen - Determine whether the next preprocessor token to be
+  /// lexed is a '('.  If so, consume the token and return true, if not, this
+  /// method should have no observable side-effect on the lexed tokens.
+  bool isNextPPTokenLParen();
+  
   /// ReadFunctionLikeMacroFormalArgs - After reading "MACRO(", this method is
   /// invoked to read all of the formal arguments specified for the macro
   /// invocation.  This returns null on error.