How to know the type of return value?

[OKMIMO]

Hi all,
When view msvbvm60.dll I have the following subrotine:
.text:734FC9F4 ; =============== S U B R O U T I N E =======================================
.text:734FC9F4
.text:734FC9F4 ; Attributes: bp-based frame
.text:734FC9F4
.text:734FC9F4 ; int __stdcall rtcCos(double)
.text:734FC9F4 public rtcCos
.text:734FC9F4 rtcCos proc near
.text:734FC9F4
.text:734FC9F4 arg_0 = qword ptr 8
.text:734FC9F4
.text:734FC9F4 push ebp
.text:734FC9F5 mov ebp, esp
.text:734FC9F7 fld [ebp+arg_0]
.text:734FC9FA fabs
.text:734FC9FC fcomp ds:dbl_7343B4E8
.text:734FCA02 fnstsw ax
.text:734FCA04 sahf
.text:734FCA05 jb short loc_734FCA0E
.text:734FCA07 push 5
.text:734FCA09 call sub_734EE086
.text:734FCA0E ; ---------------------------------------------------------------------------
.text:734FCA0E
.text:734FCA0E loc_734FCA0E: ; CODE XREF: rtcCos+11j
.text:734FCA0E fld [ebp+arg_0]
.text:734FCA11 fcos
.text:734FCA13 fstp [ebp+arg_0]
.text:734FCA16 fld [ebp+arg_0]
.text:734FCA19 pop ebp
.text:734FCA1A retn 8
.text:734FCA1A rtcCos endp
Above I look that: The return value is "int", but in fact then it's not, the rtcCos() function which works in VB6 returns "double",...
Please help me the following problems:
1. How to define the type of return value of any function in IDA (when view ASM).
2. Somewhat, to define the type of parameters of any function (exam: arg_0, arg_4,....).
Thank a lot,
Mimo

[Git]

You can do some of what you want with the usercall definition, but remember - asm knows nothing about types.

Git

[OKMIMO]

You can do some of what you want with the usercall definition, but remember - asm knows nothing about types.

Git

Hi Git,
Thank you for your informations which you provided. I'll try to understand this, I'm going to return this problem after, when that you help me! Thank again.

Mimo