Visual Studio 2010 optimized code bug

[ForNow]

Hi, Using the GetProcAdress I wanted to get the exported address of a function When it returned zero I double checked with depends.exe to ensure the function was exported I then went to assembly mode to see what happens and noticed that after the call statement a value was returned in the RAX register but there wasn't any code to move the RAX register value to my FARPROC data member I then turned optimization off #pragma optimize("",off) and the same code generated "mov FARPROC,rax" am I missing some compiler to flag to make this happen without turning optimization off Thanks Thanks

[_Superman_]

It would help if you could post the code in your function and some of the generated assembly code.

«_Superman_»  _I love work. It gives me something to do between weekends.

_Microsoft MVP (Visual C++) (October 2009 - September 2013)

Polymorphism in C

[ForNow]

Here it is HMODULE hutil_module; FARPROC hercgui_addr; hutil_module = GetModuleHandle("HENGINE"); With #pragma optimize("",off) hercgui_addr = GetProcAddress(hutil_module,"hercgui_proc"); 000000005178D4BC lea rdx,[string "hercgui_proc" (518672B0h)] 000000005178D4C3 mov rcx,qword ptr [rsp+0E0h] 000000005178D4CB call qword ptr [__imp_GetProcAddress (5184A050h)] 000000005178D4D1 mov qword ptr [rsp+0C0h],rax with optimization on hercgui_addr = GetProcAddress(hutil_module,"hercgui_proc"); 00000000514CD44B lea rdx,[string "hercgui_proc" (515A42B0h)] 00000000514CD452 mov rcx,rax 00000000514CD455 call qword ptr [__imp_GetProcAddress (51587050h)] Thanks

[bob16972]

Do you actually use

hercgui_addr

later in the code? I find that if I'm looking at optimized assembly output that if I don't actually use the value for something, the extra processing code can get discarded. At a minimum, you can dump the value to console or screen to make sure the code remains in the optimized assembly output.

[ForNow]

This is the next statement strncpy(&herc_parm[0],&hercgui_addr,8); I am running X64 I send thid address to child process

  return\_code = CreateProcess((LPCSTR) &herc\_command\[0\],    // command 
		            (LPCSTR) &herc\_parm\[0\],         // paramter
                                (LPCSTR) &sa,
                                NULL,
                                TRUE,
                                (DWORD) NULL,
                                NULL,
                                NULL,
                                &si,
                                &pi);

Later in the child process I Create a Remote thread with the parent

snap_shot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS,0);

process32.dwSize = sizeof(PROCESSENTRY32);

return_cde = Process32First(snap_shot,&process32);

pid = GetCurrentProcessId(); // Get Current process id

  while(pid != process32.th32ProcessID)

{
return_cde = Process32Next(snap_shot,&process32);
}

herc_process = process32.th32ParentProcessID;

my_herc = OpenProcess(PROCESS_ALL_ACCESS,FALSE,herc_process); // Get a Handle to
if (my_herc == NULL)
errcd= GetLastError();

SECURITY_ATTRIBUTES sa;
LPVOID lparam;
DWORD threadid;

           sa.nLength =  sizeof(sa);
           sa.lpSecurityDescriptor = NULL;
           sa.bInheritHandle = TRUE;

lparam = NULL;

        CreateRemoteThread(my\_herc,
                           &sa,
                           NULL,
                           (LPTHREAD\_START\_ROUTINE) hercgui,
                           lparam,
                           NULL,
                           &threadid);

[Lost User]

ForNow wrote:

When it returned zero I double checked with depends.exe to ensure the function was exported

Did you actually check what error was being generated, as described in the function's documentation[^]?

[ForNow]

Richard look at what happens When I turn optimazation off and check for an error no code is generated for the if (hercgui_addr = NULL) one wierd complier On aonther issue my assignment at work I was able to resolve the 800A30EC I think thats it by Doing app.GetActiveWorkBook however txt file wasn't displayed in the workbook in fact a worksheet wasn't loaded I was under the impression that OpenText loads a worksheet as well Thanks

       hercgui\_addr = GetProcAddress(hutil\_module,"hercgui\_proc");

00000000013FD44B lea rdx,[string "hercgui_proc" (14D42B0h)]
00000000013FD452 mov rcx,rax
00000000013FD455 call qword ptr [__imp_GetProcAddress (14B7050h)]

	   if (hercgui\_addr = NULL)
		    errcd = GetLastError();

[Lost User]

if (hercgui_addr = NULL)

This sets the value of hercgui_addr to NULL, so it is little wonder that the generated code does not look correct.

[ForNow]

Thanks once I referenced hercgui eith "==" the optimized version genereted the "mov hercgui,rax" Thanks again