C++: Remove workaround for crashing if parsing invalid code

This reverts the changes

    commit beac7b9539
    C++: Fix highlighting after "invalid code"

    commit 78ab287fc6
    C++: Stop parsing a declaration after two tries

which were a work around for QTCREATORBUG-12890.

A follow-up patch provides a proper fix.

Task-number: QTCREATORBUG-12890
Change-Id: I2650a8e41c8ff1180cad9f069e463fc51bd2f1b1
Reviewed-by: Erik Verbruggen <erik.verbruggen@theqtcompany.com>

src/libs/3rdparty/cplusplus/Parser.cpp

@@ -265,13 +265,12 @@ inline void debugPrintCheckCache(bool) {}
     return true; \
 }
 
-Parser::Parser(TranslationUnit *unit, int retryParseDeclarationLimit)
+Parser::Parser(TranslationUnit *unit)
     : _translationUnit(unit),
       _control(unit->control()),
       _pool(unit->memoryPool()),
       _languageFeatures(unit->languageFeatures()),
       _tokenIndex(1),
-      _retryParseDeclarationLimit(retryParseDeclarationLimit),
       _templateArguments(0),
       _inFunctionBody(false),
       _inExpressionStatement(false),
@@ -311,20 +310,6 @@ bool Parser::skipUntil(int token)
     return false;
 }
 
-void Parser::skipUntilAfterSemicolonOrRightBrace()
-{
-    while (int tk = LA()) {
-        switch (tk) {
-            case T_SEMICOLON:
-            case T_RBRACE:
-                consumeToken();
-                return;
-            default:
-                consumeToken();
-        }
-    }
-}
-
 void Parser::skipUntilDeclaration()
 {
     for (; ; consumeToken()) {
@@ -641,25 +626,19 @@ bool Parser::parseTranslationUnit(TranslationUnitAST *&node)
     TranslationUnitAST *ast = new (_pool) TranslationUnitAST;
     DeclarationListAST **decl = &ast->declaration_list;
 
-    int declarationsInRowFailedToParse = 0;
-
     while (LA()) {
         unsigned start_declaration = cursor();
 
         DeclarationAST *declaration = 0;
 
         if (parseDeclaration(declaration)) {
-            declarationsInRowFailedToParse = 0;
             *decl = new (_pool) DeclarationListAST;
             (*decl)->value = declaration;
             decl = &(*decl)->next;
         } else {
             error(start_declaration, "expected a declaration");
             rewind(start_declaration + 1);
-            if (++declarationsInRowFailedToParse == _retryParseDeclarationLimit)
-                skipUntilAfterSemicolonOrRightBrace();
-            else
-                skipUntilDeclaration();
+            skipUntilDeclaration();
         }
 
 
@@ -808,8 +787,6 @@ bool Parser::parseLinkageBody(DeclarationAST *&node)
         ast->lbrace_token = consumeToken();
         DeclarationListAST **declaration_ptr = &ast->declaration_list;
 
-        int declarationsInRowFailedToParse = 0;
-
         while (int tk = LA()) {
             if (tk == T_RBRACE)
                 break;
@@ -817,17 +794,13 @@ bool Parser::parseLinkageBody(DeclarationAST *&node)
             unsigned start_declaration = cursor();
             DeclarationAST *declaration = 0;
             if (parseDeclaration(declaration)) {
-                declarationsInRowFailedToParse = 0;
                 *declaration_ptr = new (_pool) DeclarationListAST;
                 (*declaration_ptr)->value = declaration;
                 declaration_ptr = &(*declaration_ptr)->next;
             } else {
                 error(start_declaration, "expected a declaration");
                 rewind(start_declaration + 1);
-                if (++declarationsInRowFailedToParse == _retryParseDeclarationLimit)
-                    skipUntilAfterSemicolonOrRightBrace();
-                else
-                    skipUntilDeclaration();
+                skipUntilDeclaration();
             }
 
             _templateArgumentList.clear();

src/libs/3rdparty/cplusplus/Parser.h

@@ -33,7 +33,7 @@ namespace CPlusPlus {
 class CPLUSPLUS_EXPORT Parser
 {
 public:
-    Parser(TranslationUnit *translationUnit, int retryParseDeclarationLimit);
+    Parser(TranslationUnit *translationUnit);
     ~Parser();
 
     bool parseTranslationUnit(TranslationUnitAST *&node);
@@ -254,7 +254,6 @@ public:
     bool parseDesignator(DesignatorAST *&node);
 
     bool skipUntil(int token);
-    void skipUntilAfterSemicolonOrRightBrace();
     void skipUntilDeclaration();
     bool skipUntilStatement();
     bool skip(int l, int r);
@@ -317,7 +316,6 @@ private:
     MemoryPool *_pool;
     LanguageFeatures _languageFeatures;
     unsigned _tokenIndex;
-    int _retryParseDeclarationLimit;
     bool _templateArguments: 1;
     bool _inFunctionBody: 1;
     bool _inExpressionStatement: 1;

src/libs/3rdparty/cplusplus/TranslationUnit.cpp

@@ -49,8 +49,7 @@ TranslationUnit::TranslationUnit(Control *control, const StringLiteral *fileId)
       _lastSourceChar(0),
       _pool(0),
       _ast(0),
-      _flags(0),
-      _retryParseDeclarationLimit(defaultRetryParseDeclarationLimit())
+      _flags(0)
 {
     _tokens = new std::vector<Token>();
     _comments = new std::vector<Token>();
@@ -300,7 +299,7 @@ bool TranslationUnit::parse(ParseMode mode)
 
     f._parsed = true;
 
-    Parser parser(this, _retryParseDeclarationLimit);
+    Parser parser(this);
     bool parsed = false;
 
     switch (mode) {

src/libs/3rdparty/cplusplus/TranslationUnit.h

@@ -149,9 +149,6 @@ public:
     LanguageFeatures languageFeatures() const { return _languageFeatures; }
     void setLanguageFeatures(LanguageFeatures features) { _languageFeatures = features; }
 
-    static int defaultRetryParseDeclarationLimit() { return 2; }
-    void setRetryParseDeclarationLimit(int limit) { _retryParseDeclarationLimit = limit; }
-
 private:
     struct PPLine {
         unsigned utf16charOffset;
@@ -213,8 +210,6 @@ private:
         Flags f;
     };
     LanguageFeatures _languageFeatures;
-
-    int _retryParseDeclarationLimit;
 };
 
 } // namespace CPlusPlus