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c++visual-c++wdkansi-c

Strict standards-compliance with Visual C++

This question is not the same as either of these:

I am running Windows 7 and Visual Studio Express 2012, but I expect neither to influence the answer to this question.

tl;dr How would I most appropriately counteract/prevent/tolerate the effects of the following excerpt from math.h, while still being allowed to compile with Visual C++?

#if     !__STDC__

/* Non-ANSI names for compatibility */

#define DOMAIN      _DOMAIN
#define SING        _SING
#define OVERFLOW    _OVERFLOW
#define UNDERFLOW   _UNDERFLOW
#define TLOSS       _TLOSS
#define PLOSS       _PLOSS

#define matherr     _matherr

Background: I'm writing a hobby text-based C++ project whose overall goals are far outside this question's scope. I'm using GNU Make (for familiarity and portability) to compile it with both Cygwin g++ and cl.exe, and assuming a strictly standards-compliant environment... so far. I'm beginning to think that Windows simply doesn't allow such an assumption.

I have an enum whose members include OVERFLOW and UNDERFLOW. The problem described below threatens to force me to change those names, but I would prefer to keep them because they are most appropriate for my purpose, notwithstanding outside influences such as Windows header files.

GCC, Visual C++, and Mac OS X's header files (independent of llvm-gcc) all define OVERFLOW and UNDERFLOW, among other non-standard macros, in math.h by default.

  • GCC has a selection of documented means of cleanly preventing those definitions.
  • Mac OS X has a couple of undocumented means to do the same, one of which (_POSIX_C_SOURCE) coincides with GCC's documentation. (I mention this in the interest of compensating for Apple's lack of documentation; I have a history with these identifiers.)
  • MSDN documents the /u command-line option as a means (via the __STDC__ macro) of preventing the definition of a few non-standard macros in Visual C++. As shown at the beginning of this question, the __STDC__ macro also prevents definition of OVERFLOW and UNDERFLOW.

Upon discovering that the /u switch would prevent the definitions I was concerned with, I added it to my makefile. But then I got a new error from line 44 of crtdefs.h:

error C1189: Only Win32 target supported!

This is because _WIN32 is no longer defined. A bit of searching indicated that crtdefs.h is related to the Windows Driver Development Kit. I'm not developing a driver; can I somehow not use that header? Or do I just need to rename my enum members to tolerate non-standard Windows behavior?

Solution

  • Instead of using the /u compiler switch, which has multiple effects, just use /D__STDC__=1 which causes the __STDC__ macro to be defined, and nothing else.