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Simple build questions

; int __stdcall wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPWSTR lpCmdLine, int nShowCmd)
_wWinMain@16 proc near

var_4= dword ptr -4
hInstance= dword ptr  4
hPrevInstance= dword ptr  8
lpCmdLine= dword ptr  0Ch
nShowCmd= dword ptr  10h

From what I see, the last 4 variables are parameters passed to the WinMain function. In addition, var_4 must be an int variable, declared later in the function body. Now I have a couple of questions:

a) What is the word size in a 32-bit Windows program? 4 bytes? being the word 8?

b) Why is var_4 set to -4? Why not start, say, 0?

c) The standard procedure for defining ints in c, though

var_x = dword ptr y?

thanks

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3 answers

a. Unsigned DWORD, 32 bits: see here (old name, MS started using it when Windows was 16-bit).

b. the top of the stack (dword ptr 0) is occupied by the return address

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+2

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+1

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