1.24. STRUCTURES
};
int main()
{
struct outer_struct s;
s.a=1;
s.b=2;
s.c.a=100;
s.c.b=101;
s.d=3;
s.e=4;
f(s);
};
...inthiscase,bothinner_structfieldsaretobeplacedbetweenthea,bandd,efieldsoftheouter_struct.
Let’s compile (MSVC 2010):
Listing 1.349: Optimizing MSVC 2010 /Ob0$SG2802 DB 'a=%d; b=%d; c.a=%d; c.b=%d; d=%d; e=%d', 0aH, 00H
_TEXT SEGMENT
_s$ = 8
_f PROC
mov eax, DWORD PTR _s$[esp+16]
movsx ecx, BYTE PTR _s$[esp+12]
mov edx, DWORD PTR _s$[esp+8]
push eax
mov eax, DWORD PTR _s$[esp+8]
push ecx
mov ecx, DWORD PTR _s$[esp+8]
push edx
movsx edx, BYTE PTR _s$[esp+8]
push eax
push ecx
push edx
push OFFSET $SG2802 ; 'a=%d; b=%d; c.a=%d; c.b=%d; d=%d; e=%d'
call _printf
add esp, 28
ret 0
_f ENDP
_s$ = -24
_main PROC
sub esp, 24
push ebx
push esi
push edi
mov ecx, 2
sub esp, 24
mov eax, esp
; from this moment, EAX is synonymous to ESP:
mov BYTE PTR _s$[esp+60], 1
mov ebx, DWORD PTR _s$[esp+60]
mov DWORD PTR [eax], ebx
mov DWORD PTR [eax+4], ecx
lea edx, DWORD PTR [ecx+98]
lea esi, DWORD PTR [ecx+99]
lea edi, DWORD PTR [ecx+2]
mov DWORD PTR [eax+8], edx
mov BYTE PTR _s$[esp+76], 3
mov ecx, DWORD PTR _s$[esp+76]
mov DWORD PTR [eax+12], esi
mov DWORD PTR [eax+16], ecx
mov DWORD PTR [eax+20], edi
call _f
add esp, 24
pop edi
pop esi
xor eax, eax