Am 05.09.2012 18:27, schrieb Alexander Hofmann: > Hi there. > > This is a cross-post (cross-mail ?) to > http://www.lazarus.freepascal.org/index.php/topic,17978.0.html as I got > the hint there that it might be better to ask on the list instead of in > the forum, at least concerning the calling conventions - but I'll ask > the whole lot, anyway; I hope that's ok (and, yes, I made the mistake to > ask on the Lazarus list before, so I sincerely hope I won't bother the > wrong people again, sorry) > > Question: > Is there any difference in the calling convention on x64-Systems between > Delphi and Lazarus? I could only find the "standard" information on > Windows x64 calling conventions, without special care of constructors, > if there is any.
Constructors are not part of the Win x64 ABI so any compiler is free to pass the hidden parameters needed by a constructor. > > The reason why I'm asking is the following: > I'm trying to get PascalScript running (completely, it does up to some > extend) on Win x64. I had to do some changes in x64.inc, see below - but > as far as I know, that should work - and it does, for all kinds of > calls, except calling constructors on Components. > Scripts like the following will crash the Program with a SIGSEGV. > > |program Script; > var > f:TForm; > b:TButton; > begin > f:=TForm.CreateNew(nil); //<- Works > b:=TButton.Create(f); //<- crash > b.Parent:=f; > f.Show; > end.| > > > Crash in the Program is here: > > |CLASSES_TCOMPONENT_$__INSERTCOMPONENT$TCOMPONENT > 000000000044F900 4883ec38 sub $0x38,%rsp > 000000000044F904 48895c2420 mov %rbx,0x20(%rsp) > 000000000044F909 4889742428 mov %rsi,0x28(%rsp) > 000000000044F90E 4889cb mov %rcx,%rbx > 000000000044F911 4889d6 mov %rdx,%rsi > 000000000044F914 4889da mov %rbx,%rdx > 000000000044F917 4889f1 mov %rsi,%rcx > 000000000044F91A 4889f0 mov %rsi,%rax > 000000000044F91D 488b00 mov (%rax),%rax > 000000000044F920 ff9068010000 callq *0x168(%rax) <-- crash| > > > The same Script runs fine when the Application was compiled with x86 > Lazarus 1.0. By the way: creating a TObject with e.g. o:=TObject.Create > doesn't break at al. > > Interestingly (and that is how I came to ask about the calling > conventions), when I start debugging > <SomeClass>.Create(aOwner:TComponent)-Type of Constructors, there is > some difference in the Register values, depending on whether the > Constructor was called from "pure" FPC-Code or the Script (at least so > it seems): > > o Called from FPC: rcx: 0 (nil), rdx: Class Reference, r8: Value of aOwner > o Called from Script: rcx: Class Reference, rdx: 1 (!?), r8: Value of > aOwner (at least so it seems) You need to adapt PascalScript appropriately then: probably similiar code to x86.inc:534+ needs to be added to x64.inc around 582. _______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
