疑问:debug 模式和release模式下编译出的代码不一样,原因不明

就一句代码: pPos = strrchr(pPos++,'.'); debug 和release下的编译出代码不同,导致了错误,假设执行此函数前pPos指向字符串 ".rm"

debug 下代码及反汇编:

 pPos = strrchr(pPos++,'.');
1001538A  mov         eax,dword ptr [pPos]
10015390  mov         dword ptr [ebp-1DCh],eax
10015396  mov         ecx,dword ptr [pPos]
1001539C  add         ecx,1
1001539F  mov         dword ptr [pPos],ecx
100153A5  push        2Eh 
100153A7  mov         edx,dword ptr [ebp-1DCh]
100153AD  push        edx 
100153AE  call        strrchr (10047970h)
100153B3  add         esp,8
100153B6  mov         dword ptr [pPos],eax 
 

Release 下代码及反汇编:

 pPos = strrchr(pPos++,'.');
1000B943  mov         eax,dword ptr [pPos]
1000B949  mov         dword ptr [ebp-0E0h],eax
1000B94F  push        2Eh 
1000B951  mov         ecx,dword ptr [ebp-0E0h]
1000B957  push        ecx 
1000B958  call        strrchr (10022E60h)
1000B95D  add         esp,8
1000B960  mov         dword ptr [pPos],eax
1000B966  mov         edx,dword ptr [pPos]
1000B96C  add         edx,1
1000B96F  mov         dword ptr [pPos],edx  

debug下的代码执行完后 pPos为"rm",release下为"m"

原因在于debug下先执行++ 操作,release后执行++操作,原因不明,查找中,如果哪位知道请说明下

测试代码:

int APIENTRY _tWinMain(HINSTANCE hInstance,
                     HINSTANCE hPrevInstance,
                     LPTSTR    lpCmdLine,
                     int       nCmdShow)
{
 char* pText = "c://test.rm";
 char* pPointer = NULL;

 pPointer = pText;
 pPointer = strrchr(pPointer++,'.');
 MessageBox(0,pPointer,NULL,0);

 return (int)0;
}

编译器:VS.NET 2003