Memory leaks in Tokyo 10.2.3 for linux and RO 9.4.109.1375

DonaldShimoda · July 13, 2018, 2:05pm

Have two projects compiled with delphi for Linux64, both works fine but both have evident memory leaks. Same projects compiled for Delphi has no memory leaks. Can i send one of them if support find some problem in RO libs, maybe?

Best regards.

EvgenyK · July 16, 2018, 4:50am

do you mean that projects if they are compiled for windows haven’t memory leaks but compiled for linux64 have memory leaks?

DonaldShimoda · July 16, 2018, 12:51pm

Yes, that was i mean. Complete project sent to support email.

DonaldShimoda · August 7, 2018, 3:54pm

Evgeny do you check the code?

Another doubt, according to this information:

http://docwiki.embarcadero.com/RADStudio/Tokyo/en/Automatic_Reference_Counting_in_Delphi_Mobile_Compilers

On linux (or in ARC COMPILERS) must use DisposeOf in place of plain free.

I see the generated Intf Files still use .Free, by sample:

  if lFreeStream then begin
    __response.Free();
  end;

Im wrong?

Maybe that is causing the memory leaks.

Best regards.

mh · August 7, 2018, 7:39pm

One way to find out?

EvgenyK · August 8, 2018, 6:26am

this code was used in _Async methods like Retrieve_Sum/Retrieve_GetServerTime.
I’m pretty sure that you don’t use them.

if you check sources, e.g. source\rtl\common, you will see that they mostly use Free method instead of DisposeOf.

From your link, they suggest to use this style:

Coding style changes

Because the new mobile compilers support automatic reference counting, the code can be simplified significantly when you need to refer to temporary objects within a method. Memory management is ignored completely:
class procedure TMySimpleClass.CreateOnly; 
var 
  MyObj: TMySimpleClass; 
begin 
  MyObj := TMySimpleClass.Create; 
  MyObj.DoSomething; 
end;
In the example seen above, the destructor for object is called as the program reaches the end statement, that is when the MyObj variable goes out of scope.

Can you specify what exactly ROD objects causes memory leaks, pls?

We had some places in RO code where compiler said

H2593 Code has no effect. Compiler generated temporary variable is cleared instead

probably, compiler did memory leaks in these lines …

Will recheck those lines

EvgenyK · August 8, 2018, 12:45pm

I’ve fixed some lines in code. it will be in the next beta

DonaldShimoda · August 8, 2018, 3:08pm

Sadly is a headeache to find in delphi for linux compiler… I only can say the final result is memory wasting.

DonaldShimoda · August 18, 2018, 7:08pm

Are in release DA 1379?

Any chance to have acceso to pacthed files only between latest stable release and actual beta? Just suggestions.

Best regards.

DonaldShimoda · August 19, 2018, 1:21am

Im checking the code of the beta 1379, seems like theres a bug here. Must be I but was changed to i, is ok?

Please confirm

DonaldShimoda · August 19, 2018, 4:03am

Still cant fix the memory leak. Maybe the problem is on the manipulation of the json parser

soJsonData := TROJSONValue.Create(jdtObject);

Any special considerations/recomendations on the use of that class under ARC?

apk_fields := soJsonPackage.FindItem('pk_fields').ASArray;
apk_field_item := apk_fields.Items[posCampo].AsObject;

Best regards

EvgenyK · August 20, 2018, 7:02am

thx. fixed.

this is pretty simple class and it shouldn’t cause any leaks.

DonaldShimoda · August 20, 2018, 12:23pm

Evgeny, i check everithing. Can send you the project to support? Is not a large project, pretty simple.

EvgenyK · August 20, 2018, 12:24pm

yes, you can.
pls check that it doesn’t use 3rd party libraries , like DevEx, etc

DonaldShimoda · August 20, 2018, 12:50pm

Use Unidac. Can test with trial?

EvgenyK · August 20, 2018, 12:57pm

yep, unidac is ok

DonaldShimoda · August 20, 2018, 1:30pm

Sent. thanks!

DonaldShimoda · August 28, 2018, 4:24pm

Have no news about that. Can you check?

Another questions or doubts.

In this case

var
  dw               : TDAWhereBuilder;
begin

        Contratos := SchemaGetDataset(lConexionFacturar, ServerDataModule.Schema, nme_contratos, fld_contratos_fecha, True);
        dw        := Contratos.DynamicWhere;

must be dw be defined as weak reference in Delphi ARC Compiler?

i have a lot of that kind of shorcuts references, maybe this is causing leaks?

Best regards.

DonaldShimoda · August 28, 2018, 11:12pm

I find the reason for memory leak (on delphi for linux compiler)

var
  soJsonData        : TROJSONValue;
  soJsonPackage     : TROJSONObject;
  apk_fields        : TROJSONArray;

  soJsonData   := TROJSONValue.Create(jdtObject);
(soJsonData.RefCount = 1)
  soJsonPackage     := soJsonData.AsObject;
(soJsonPackage.refCount = 2) (???)
 apk_fields := soJsonPackage.FindItem('pk_fields').ASArray;
   (apk_fields.refCount = 2) (???)

Im wrong? or something is very wrong with the library?

Best regards

EvgenyK · August 29, 2018, 7:34am

Delphi compiler should recognize local variables like dw and it should decrease refcount at exiting from this method, however you can assign nil manually when this variable isn’t required.

btw, have you called table.DynamicWhere.Clear; or table.DynamicWhere.Expression.Free; before assigning new expression into table.DynamicWhere.Expression ?

I think, these is no memory leak present: one reference is stored in TROJSONValue.FObject and second one - in soJsonPackage (local variable)