Cheat Engine

Deltron Z · Posted: Sun Sep 26, 2010 4:40 pm Post subject: Small file size - Visual Studio

I'm trying to make a small executable as possible, but visual studio is giving me a hard time doing so.
I've disabled runtime checks, stack cookies, eliminated unreferenced data, set optimization with favor small code, etc. but there are a few things I can't figure out.
First of all, the file generated contains "sort-of" junk code, it's some sort of initialization, calls to GetSystemTimeAsFileTime, GetTickCount, QueryPerformanceCounter, GetStartupInfo, GetCurrentProcessId, GetCurrentThreadId and such which I'm not planning to use in my program. I was wondering if there's any option that allows me to generate a small file that it's entry point is the main function, without any initializations, so whatever I write is whatever I get. I know I can edit the file or write the program in assembly, but I prefer writing it in C/C++.
I've also noticed that the program links to msvcxx.dll, depending on the visual studio version, which is the runtime library. I don't want to use the C-Runtime Library, even when I'm not using it my program links to something like 50 functions in it, and when I set the runtime library option to Multithreaded (/MT) the file size increases by 1000% (from a few KB to something between 30~70KB, it varies depending on the functions used), so I wonder how can I prevent visual studio from linking CRT to my program? I guess if I'll understand how to prevent from it adding "junk" initializations code to my program it'll answer this question as well...

smartz993 · Posted: Sun Sep 26, 2010 11:35 pm Post subject:

Project Properties->Linker->Advanced->Entry Point - Set to whatever your main function is.

Compile in release mode.

tada.

atom0s · Posted: Mon Sep 27, 2010 9:27 am Post subject:

Depending on how large your project is and what it uses function wise, you are going to start getting issues if you reset the entry point and use other tricks to force your executable to a smaller size.

Just use a packer and zip/rar/7zip/etc. your end result if you want a smaller executable in the end.

Deltron Z · Posted: Mon Sep 27, 2010 10:05 am Post subject:

tombana · Posted: Mon Sep 27, 2010 1:36 pm Post subject:

hcavolsdsadgadsg · Posted: Mon Sep 27, 2010 3:03 pm Post subject:

Don't count on using STL functions and keeping it tiny. msvcrt happens to be a system file though, so you can dynamically link against it.

Just keep in mind you'll need to create your own main function and handle the entry yourself. By default, your linker will look for mainCRTStartup (or WinMainCRTStartup)

You shouldn't run into issues if you stick purely to CRT functions and Win32 stuff.

Jani · Posted: Tue Sep 28, 2010 12:43 pm Post subject:

/nodefaultlibs. Or ignore default libs as in written option in the linker preferences