Print Page - how to define wsprintfA or W to work with x64calling.inc

Title: how to define wsprintfA or W to work with x64calling.inc
Post by: GUAN DE DIO on August 01, 2008, 10:40:46 PM

Hi,

I am using the x64calling.inc file and I had the next error when I tray to use wsprintfA API.

error A2052: forced error : wsprintf doesn't take this number of parameters

I have define the API in this way

funcproto external,wsprintf,QWORD,QWORD,VARARG

I spouse the problem is in VARARG.

Do anyone know how to define this kind of APIS with numbers of param variables ?

Thanks,
GUAN

Title: Re: how to define wsprintfA or W to work with x64calling.inc
Post by: GregL on August 02, 2008, 02:04:10 AM

Maybe try using a C compiler that supports x64 and look at the generated assembly code. Pelle's C supports x64 now.

Title: Re: how to define wsprintfA or W to work with x64calling.inc
Post by: ecube on March 30, 2009, 06:18:28 PM

wsprintf is a c calling convention,(cdecl) that macro is a typical 64bit callin(fastcall) so it won't work correctly.

Title: Re: how to define wsprintfA or W to work with x64calling.inc
Post by: GregL on March 30, 2009, 10:08:37 PM

E^cube,

wsprintf is fastcall in x64. The x64 C Run-Time library is fastcall too, not cdecl. There is only one calling convention.

You call wsprintf like this (copied from working code):

Code Select


  lea rcx, szBuffer  ; buffer
  lea rdx, szFmt     ; format string
  mov r8, qwNum      ; value
  call wsprintfA

I am not familiar with the funcproto macro, so I don't know why it wouldn't work, maybe it is because of VARARG.

Title: Re: how to define wsprintfA or W to work with x64calling.inc
Post by: Igor on April 02, 2009, 01:20:33 AM

Try it with only one QWORD: "funcproto external,wsprintf,QWORD,VARARG".

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Project Support Forums => 64 Bit Assembler => Topic started by: GUAN DE DIO on August 01, 2008, 10:40:46 PM