Using $IF near an attribute results in incorrect behavior

takepoi · April 13, 2019, 5:12pm

Hi.

[DllExport(‘TestFunc’)]
{$IF NOT WINDOWS}
[CallingConvention(CallingConvention.Cdecl)]
{$ENDIF}
class method TestFunc: LongInt;

This way, the DllExport attribute does not work and the function is not exported.
And also,

{$IF WINDOWS}
[DllExport(‘TestFunc’)]
{$ELSE}
[DllExport(’_TestFunc’)]
[CallingConvention(CallingConvention.Cdecl)]
{$ENDIF}
class method TestFunc: LongInt;

This way too, Windows is the target but the first DllExport attribute does not work.
I think that probably the same problem will occur with other attributes as well as DllExport.

Elements version 10.0.0.2385

RemObjectsSoftware · April 13, 2019, 9:06pm

Thanks, logged as bugs://82359

ck · April 15, 2019, 6:35am

Can you tell me what goes wrong? If I do:

unit issue82359_iftest;
interface

[DllExport('TestFunc')]
{$IF NOT WINDOWS}
[CallingConvention(CallingConvention.Cdecl)]
{$ENDIF}
 method TestFunc: LongInt; begin end;

{$IF WINDOWS}
[DllExport('TestFunc2')]
{$ELSE}
[DllExport('_TestFunc2')]
[CallingConvention(CallingConvention.Cdecl)]
{$ENDIF} 
 method TestFunc2: LongInt; begin end;

implementation

begin
    
end.

it exports:

which seems to be right?

RemObjectsSoftware · April 15, 2019, 6:37am

bugs://82359 got closed with status cannotrepro (Will reopen if needed)

takepoi · April 15, 2019, 7:11am

Write the method in the implementation section.
In the interface section, I could not write a var declaration like Delphi.

method TestFunc: LongInt;
var
l_var: LongInt;
begin
end;

Therefore, I moved the method to the implementation section.

ck · April 15, 2019, 7:32am

Right but that would not have effect on the actual code generation. Can you should an example of what doesn’t work?

takepoi · April 15, 2019, 8:05am

The problem is reproduced if you write the method in the implementation section.

If you write it in the interface section, there is no problem.

ck · April 15, 2019, 8:17am

What am I missing?

takepoi · April 15, 2019, 8:49am

Attributes are also write in the implementation section.

For example,

namespace test;
interface

implementation

[DllExport]
{$IF NOT WINDOWS}
[CallingConvention(CallingConvention.Cdecl)]
{$ENDIF}
method TestFunc: LongInt;
begin
end;
end.

RemObjectsSoftware · April 15, 2019, 9:06am

bugs://82359 got reopened.

ck · April 15, 2019, 9:10am

Got it. Fixed! thanks

RemObjectsSoftware · April 15, 2019, 9:10am

bugs://82359 got closed with status fixed.