What comes first - stack unwinding or copying of return values

Question

Is the mutex used in method GetValues() released before or after copy constructing the dummy instance?

Answer 1

As of Visual C++, using MSVC 9.0, the following code

int add(int x, int y)
{
    int z;
    z = x + y;
    return z;
}

int _tmain(int argc, _TCHAR* argv[])
{
    add(10, 20);
    return 0;
}

results in assembly

int add(int x, int y)
{
013613A0  push        ebp  //save the frame pointer
013613A1  mov         ebp,esp 
013613A3  sub         esp,0CCh 
013613A9  push        ebx  
013613AA  push        esi  
013613AB  push        edi  
013613AC  lea         edi,[ebp-0CCh] 
013613B2  mov         ecx,33h 
013613B7  mov         eax,0CCCCCCCCh 
013613BC  rep stos    dword ptr es:[edi] 
    int z;
    z = x + y;
013613BE  mov         eax,dword ptr [x] //load x
013613C1  add         eax,dword ptr [y] //add y to x
013613C4  mov         dword ptr [z],eax //store the result to z
    return z;
013613C7  mov         eax,dword ptr [z] //store the return value in eax
}
013613CA  pop         edi  //unwind the stack
013613CB  pop         esi  
013613CC  pop         ebx  
013613CD  mov         esp,ebp 
013613CF  pop         ebp  
013613D0  ret

int _tmain(int argc, _TCHAR* argv[])
{    
013613E0  push        ebp  
013613E1  mov         ebp,esp 
013613E3  sub         esp,0C0h 
013613E9  push        ebx  
013613EA  push        esi  
013613EB  push        edi  
013613EC  lea         edi,[ebp-0C0h] 
013613F2  mov         ecx,30h 
013613F7  mov         eax,0CCCCCCCCh 
013613FC  rep stos    dword ptr es:[edi] 
    add(10, 20);
013613FE  push        14h  
01361400  push        0Ah  
01361402  call        add (136109Bh) 
01361407  add         esp,8 
    return 0;
0136140A  xor         eax,eax //store 0 to eax, the return value holder
}
0136140C  pop         edi  //unwind the stack
0136140D  pop         esi  
0136140E  pop         ebx  

This makes me say that return value is stored first and then the stack unwinding happens!