diff --git a/components/codetools/customcodetool.pas b/components/codetools/customcodetool.pas
index e1fe122c86..97c5c7467b 100644
--- a/components/codetools/customcodetool.pas
+++ b/components/codetools/customcodetool.pas
@@ -190,9 +190,9 @@ type
       ExceptionOnNotFound: boolean): TCodeTreeNode;
     function CaretToCleanPos(Caret: TCodeXYPosition;
         var CleanPos: integer): integer;  // 0=valid CleanPos
-              //-1=CursorPos was skipped, CleanPos between two links
-              // 1=CursorPos beyond scanned code
-              //-2=X,Y beyond source
+                          //-1=CursorPos was skipped, CleanPos between two links
+                          // 1=CursorPos beyond scanned code
+                          //-2=X,Y beyond source
     function CleanPosToCodePos(CleanPos: integer;
         out CodePos:TCodePosition): boolean; // true=ok, false=invalid CleanPos
     function CleanPosToCaret(CleanPos: integer;
@@ -1655,17 +1655,17 @@ function TCustomCodeTool.IgnoreErrorAfterPositionIsInFrontOfLastErrMessage: bool
 var
   IgnoreErrorAfterCleanPos: integer;
 begin
-  DebugLn('TCustomCodeTool.IgnoreErrorAfterPositionIsInFrontOfLastErrMessage ',
-    ' LastErrorCheckedForIgnored='+dbgs(LastErrorCheckedForIgnored),
-    ' LastErrorBehindIgnorePosition='+dbgs(LastErrorBehindIgnorePosition));
+  //DebugLn('TCustomCodeTool.IgnoreErrorAfterPositionIsInFrontOfLastErrMessage ',
+  //  ' LastErrorCheckedForIgnored='+dbgs(LastErrorCheckedForIgnored),
+  //  ' LastErrorBehindIgnorePosition='+dbgs(LastErrorBehindIgnorePosition));
   if LastErrorCheckedForIgnored then begin
     Result:=LastErrorBehindIgnorePosition;
   end else begin
     if (Scanner<>nil) then begin
       IgnoreErrorAfterCleanPos:=Scanner.IgnoreErrorAfterCleanedPos;
-      DebugLn('  IgnoreErrorAfterCleanPos='+dbgs(IgnoreErrorAfterCleanPos)+'"'+copy(Src,IgnoreErrorAfterCleanPos-6,6)+'"',
-        ' LastErrorCurPos.StartPos='+dbgs(LastErrorCurPos.StartPos)+'"'+copy(Src,LastErrorCurPos.StartPos-6,6)+'"',
-        ' LastErrorPhase>CodeToolPhaseParse='+dbgs(LastErrorPhase>CodeToolPhaseParse));
+      //DebugLn('  IgnoreErrorAfterCleanPos='+dbgs(IgnoreErrorAfterCleanPos)+'"'+copy(Src,IgnoreErrorAfterCleanPos-6,6)+'"',
+      //  ' LastErrorCurPos.StartPos='+dbgs(LastErrorCurPos.StartPos)+'"'+copy(Src,LastErrorCurPos.StartPos-6,6)+'"',
+      //  ' LastErrorPhase>CodeToolPhaseParse='+dbgs(LastErrorPhase>CodeToolPhaseParse));
       if IgnoreErrorAfterCleanPos>0 then begin
         // ignore position in scanned code
         // -> check if last error is behind ignore position
@@ -1883,7 +1883,7 @@ begin
   FIgnoreErrorAfter:=AValue;
   LastErrorCheckedForIgnored:=false;
   {$IFDEF ShowIgnoreErrorAfter}
-  DebugLn('TCustomCodeTool.SetIgnoreErrorAfter ',dbgsCP(FIgnoreErrorAfter));
+  DebugLn('TCustomCodeTool.SetIgnoreErrorAfter FIgnoreErrorAfter=',dbgsCP(FIgnoreErrorAfter));
   {$ENDIF}
   if Scanner<>nil then
     Scanner.SetIgnoreErrorAfter(IgnoreErrorAfter.P,IgnoreErrorAfter.Code);
diff --git a/components/codetools/linkscanner.pas b/components/codetools/linkscanner.pas
index ecf5ff9ca4..8da8a73911 100644
--- a/components/codetools/linkscanner.pas
+++ b/components/codetools/linkscanner.pas
@@ -1490,8 +1490,8 @@ var
   CleanResult: integer;
 begin
   //DebugLn('TLinkScanner.IgnoreErrAfterPositionIsInFrontOfLastErrMessage');
-  //DebugLn('  LastErrorCheckedForIgnored=',LastErrorCheckedForIgnored,
-  //  ' LastErrorBehindIgnorePosition=',LastErrorBehindIgnorePosition);
+  //DebugLn(['  LastErrorCheckedForIgnored=',LastErrorCheckedForIgnored,
+  //  ' LastErrorBehindIgnorePosition=',LastErrorBehindIgnorePosition]);
   if LastErrorCheckedForIgnored then
     Result:=LastErrorBehindIgnorePosition
   else begin
@@ -1500,9 +1500,11 @@ begin
     begin
       CleanResult:=CursorToCleanPos(FIgnoreErrorAfterCursorPos,
                          FIgnoreErrorAfterCode,CleanedIgnoreErrorAfterPosition);
-      //DebugLn('  CleanResult=',CleanResult,
+      //DebugLn(['  CleanResult=',CleanResult,
       //  ' CleanedIgnoreErrorAfterPosition=',CleanedIgnoreErrorAfterPosition,
-      //  ' FIgnoreErrorAfterCursorPos=',FIgnoreErrorAfterCursorPos);
+      //  ' FIgnoreErrorAfterCursorPos=',FIgnoreErrorAfterCursorPos,
+      //  ' CleanedLen=',CleanedLen,
+      //  ' LastErrorIsValid=',LastErrorIsValid]);
       if (CleanResult=0) or (CleanResult=-1)
       or (not LastErrorIsValid) then begin
         Result:=true;
@@ -2754,7 +2756,7 @@ begin
       //DebugLn('[TLinkScanner.CursorToCleanPos] B ACleanPos=',ACleanPos);
       if i+1<LinkCount then begin
         // link has successor
-        //DebugLn('[TLinkScanner.CursorToCleanPos] C Links[i+1].CleanedPos=',Links[i+1].CleanedPos);
+        //DebugLn(['[TLinkScanner.CursorToCleanPos] C Links[i+1].CleanedPos=',Links[i+1].CleanedPos]);
         if ACleanPos<FLinks[i+1].CleanedPos then begin
           // link covers the cursor position
           Result:=0;  // valid position
@@ -2782,8 +2784,8 @@ begin
         i:=j-1;
       end else begin
         // in last link
-        //DebugLn('[TLinkScanner.CursorToCleanPos] E length(FCleanedSrc)=',length(FCleanedSrc));
-        if ACleanPos<=length(FCleanedSrc) then begin
+        //DebugLn(['[TLinkScanner.CursorToCleanPos] E ACleanPos=',ACleanPos,' CleanedLen=',CleanedLen]);
+        if ACleanPos<=CleanedLen then begin
           Result:=0;  // valid position
           exit;
         end;
@@ -2969,6 +2971,7 @@ begin
   LastErrorSrcPos:=SrcPos;
   LastErrorCode:=Code;
   LastErrorCheckedForIgnored:=false;
+  LastErrorIsValid:=true;
   raise ExceptionClass.Create(Self,AMessage);
 end;
 
diff --git a/components/codetools/pascalparsertool.pas b/components/codetools/pascalparsertool.pas
index 9d4f56a5a4..46c7488dea 100644
--- a/components/codetools/pascalparsertool.pas
+++ b/components/codetools/pascalparsertool.pas
@@ -3769,15 +3769,15 @@ begin
   end
   else if not (btKeepIgnoreErrorPos in BuildTreeFlags) then
     ClearIgnoreErrorAfter;
-    
-  if (TreeRange=trTillCursor) and (not UpdateNeeded(true)) then begin
-    // interface tree is valid
+
+  if (TreeRange=trTillCursor) and (not UpdateNeeded(false)) then begin
+    // tree is valid
     // -> if there was an error, raise it again
     if (LastErrorPhase in [CodeToolPhaseScan,CodeToolPhaseParse])
     and ((not IgnoreErrorAfterValid)
       or (not IgnoreErrorAfterPositionIsInFrontOfLastErrMessage))
     then begin
-      //DebugLn('TPascalParserTool.BuildTreeAndGetCleanPos RaiseLastError ',MainFilename);
+      DebugLn('TPascalParserTool.BuildTreeAndGetCleanPos RaiseLastError ',MainFilename);
       RaiseLastError;
     end;
     // check if cursor is in interface