Thread: A lot of warnings C4003 & errors C2059 after using VC's native CRT Debugger

Hi, currently in my bug hunting endeavor, I am stumbled on some errors. I tried implementing the VC's native CRT debugger / memory leak detector from this web: http://msdn.microsoft.com/en-us/libr...h3(VS.80).aspx. But now I can't compile my code because it produces lots of warnings C4003 & errors C2059 like the quote below:

19>c:\convex.h(109) : warning C4003: not enough actual parameters for macro 'free'
19>c:\convex.h(109) : error C2059: syntax error : ','

It seems like there's a 'free' macro that has already been defined. But the funny thing is, all of the instance of 'free' are regarded as errors. Even if they are a member function of a class. For example, the above quoted error is from a member function of a Convex class (as in "Convex::free()" ). How do I solve this besides having to undef the macro? I mean, if I undef-ed the macro, what's the point of using the CRT debugger / memory leak detector in the first place, right?

Thanks a lot in advance.

Show us the code (the macro or whatever).

--
Mats

It seems to me that you would have to push the macro, undef it, then pop the macro where appropriate. Macros are evil; which is also why they are typically avoided.

First, thank you for the replies guys.

Originally Posted by matsp

Show us the code (the macro or whatever).

--
Mats

Well, this is from crtdbg.h

Code:

#ifdef  _CRTDBG_MAP_ALLOC

#define   malloc(s)             _malloc_dbg(s, _NORMAL_BLOCK, __FILE__, __LINE__)
#define   calloc(c, s)          _calloc_dbg(c, s, _NORMAL_BLOCK, __FILE__, __LINE__)
#define   realloc(p, s)         _realloc_dbg(p, s, _NORMAL_BLOCK, __FILE__, __LINE__)
#define   _recalloc(p, c, s)    _recalloc_dbg(p, c, s, _NORMAL_BLOCK, __FILE__, __LINE__)
#define   _expand(p, s)         _expand_dbg(p, s, _NORMAL_BLOCK, __FILE__, __LINE__)
#define   free(p)               _free_dbg(p, _NORMAL_BLOCK)
...
#endif  /* _CRTDBG_MAP_ALLOC */

I think it is used to wrap the new, delete, malloc, realloc, calloc, free, etc so that it will keep a record of the values of the memory being allocated, is it freed in the end or not, etc. Just like a memory leak detector / profiler. And it is native in Visual C++ (AFAIK).

Originally Posted by Elysia

It seems to me that you would have to push the macro, undef it, then pop the macro where appropriate. Macros are evil; which is also why they are typically avoided.

That would mean re-writing the whole 400+ header and source files with 2000+ lines of code each (in average). Great.

Is there any other easier way?

Thanks again.

> That would mean re-writing the whole 400+ header and source files with 2000+ lines of code each (in average).
And that would indeed be a big mistake.

Did you heed this warning on the usage of crtdbg?

Originally Posted by msdn

The #include statements must be in the order shown here. If you change the order, the functions you use may not work properly.

I use this quite a lot, so there's probably something messed up with the general usage, rather than any specific instance of calling free().

How do I solve this besides having to undef the macro?

You can push/pop the macro before/after the Convex header.
You can modify the header to avoid the macro:

Code:

#define NMS /* No Macro Substitution */
free NMS ();

@all

Okay, I've moved the #include statement just before the main() function ( the last #include statement before main() ). And it's working, I think. Thanks a lot guys.