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delphiwindows-8app-certification-kitwack

Can a desktop Delphi application be certified for Windows 8 (using Windows App Certification Kit)?

Apparently, Delphi (any version) does not support safe exception handlers (/SAFESEH switch in Visual Studio). This results in a warning when using Windows Desktop App Certification Kit on Windows 8. Per certification requirements for Windows 8 desktop apps:

Your app must be compiled using the /SafeSEH flag to ensure safe exceptions handling

Obviously Delphi lacks this switch, so it cannot be done. My questions are:

  1. Is my understanding correct, that even though the Kit displays only a warning (not fail), since this is a "must" requirement, any Delphi app today cannot be certified for Windows 8 and therefore cannot be included in the Windows app store?

  2. Can SafeSEH tables be added to a PE file after the compilation somehow (e.g. extracting needed info from the map file or debug symbols), or we absolutely need a compiler/linker support for this, and therefore must wait till Embarcadero implements this feature?

To clearify, my application is Windows 32-bit desktop application (64-bit compatible), not Metro application.

Solution

  • I cannot answer question 1. However, I find it hard to imagine that the use of the word must could mean that the rule was optional.

    As for question 2, you would need support from the compiler/linker. You cannot reasonably expect to back fit this with a PE editing post-link tool. Consider the following code:

    try
  Beep;
except
  on E: Exception do
    Writeln(E.ClassName, ': ', E.Message);
end;

    The compiler emits the following:

    Project1.dpr.11: try
0041C3AA 33C0             xor eax,eax
0041C3AC 55               push ebp
0041C3AD 68C9C34100       push $0041c3c9 // exception handler is at $0041c3c9
0041C3B2 64FF30           push dword ptr fs:[eax]
0041C3B5 648920           mov fs:[eax],esp
Project1.dpr.12: Beep;
0041C3B8 6A00             push $00
0041C3BA E8E1CEFEFF       call MessageBeep
0041C3BF 33C0             xor eax,eax
0041C3C1 5A               pop edx
0041C3C2 59               pop ecx
0041C3C3 59               pop ecx
0041C3C4 648910           mov fs:[eax],edx
0041C3C7 EB59             jmp $0041c422
0041C3C9 E97291FEFF       jmp @HandleOnException
0041C3CE 0100             add [eax],eax
0041C3D0 0000             add [eax],al
0041C3D2 E42F             in al,$2f
0041C3D4 41               inc ecx
0041C3D5 00DA             add dl,bl
0041C3D7 C3               ret 
0041C3D8 41               inc ecx
0041C3D9 00A3D83E4200     add [ebx+$00423ed8],ah
Project1.dpr.15: Writeln(E.ClassName, ': ', E.Message);
........

    Now, the real exception handler is HandleOnException, implemented in System.pas. But, the address pushed onto the stack is $0041c3c9, an address local to the code containing the try/except block. This means that in order to create a SafeSEH PE section you would need to locate each and every try/except in your code. Whilst that is obviously feasible, I don't think it is tractable.

    I rather imagined that the SEH exception handlers for the x86 compiler would be just the _HandleXXX functions declared in System.pas. In which case it would be easy enough to add a PE section listing just those functions as a post-link step. However, since every single try/except has its own local exception handler, I now believe that only the compiler author can realistically hope to add the SafeSEH PE section.

    There is, so far as I can see, no QC report that requests SafeSEH support for the x86 Windows compiler. I suggest that you log a QC report, and an official support case.

    Update: Well done to @haimg for succeeding where I failed and managing to locate a QC report: QC#106781.