Run-Time Check Failure #0

[EKACHITH]

Hi I have developed very small program for calculation, and in that I have included my personal DLL files that I have created. The DLL files contains the code

extern "A" declspec(dllexport)
int fact(int n)
{
	double j, fac;
	for(j = 2, fac = 1; j <= n; j++)
		fac*=j;
	return fac;
}

And I am calling those DLL files from my program and while compiling the code I am getting the error like “Run-Time Check Failure #0 The value of ESP was not properly , any suggestion?

[Steyn]

This is typically occur while you have the incorrect calling convention on functions, I mean to say there might be some spelling mistake in the your programs thus you’re having this problems, and this is generally occurs due to the lines declspec (dLL---) or this is also possible that you have build the DLL next to the incorrect runtime libraries. So my recommendation is same as you should first of all check all the things in the coding like is properly written.

[Vandam]

The DLL that you have declared is might be having a number of a dissimilar calling convention than the function pointer, and in C++ let me tell you that there are two calling conventions and they are cdecl and stdcall, I would suggest you that you must have to declare your function pointer to be equivalent as the correct calling convention as your DLL function.

[EKACHITH]

OK let me tell you about the other code also which actually causing these error, see actually I am using WINAPI in the program and the program is actually to calculate the factorial of the given number, and in that in the main function the line i = fact(5); is causing the actual error, even though there is error, but program calculate the value perfectly.

[Jacques25]

Yeah I got your problem, the error is not actually there I would say as you have mentioned your developed DLL, there is the Problem because as far as I know C++ has only two calling convention that is mentioned by the above user, and It seems you have used the incorrect one in your DLL, because as far as I know the WINAPI contains stdcall, whereas In your DLL you had used cdecl function, so first of all change that and then see whether the problem happens or not.

[EKACHITH]

Hey thanks for giving the suggestion as according to your mentioned one i have changed those values in the programs but after that the first error was solved but I got some another error like

warning C4518: 'int ' : storage-class or type specifier(s) unexpected here

warning C4230: anachronism used : modifiers/qualifiers interspersed

and it says not able to load the function fact, now what can I do next?

[Ronchi]

Answer6- Follow this code for finding the factorial of the program

extern "A" int declspec(dllexport) stdcall
fact(int n)
{
	int i, fac;
	for(i = 2, fac = 1; i <= n; i++)
		fac*=i;
	return fac;
}

After that you can call this DLL through actual name of the DLL not the one that you have mentioned, and to see that name you can use the Dependency Walker utility.