Question

When creating custom typedefs for integers, is it possible for compiler to warn when you when using a default numeric type?

For example,

typedef int_fast32_t    kint;

int_fast32_t test=0;//Would be ok
kint test=0; //Would be ok
int test=0; //Would throw a warning or error

We’re converting a large project and the default int size on platform is 32767 which is causing some issues. This warning would warn a user to not use ints in the code.

If possible, it would be great if this would work on GCC and VC++2012.

Answer 1

I’m reasonably sure gcc has no such option, and I’d be surprised if VC did.

I suggest writing a program that detects references to predefined types in source code, and invoking that tool automatically as part of your build process. It would probably suffice to search for certain keywords.

Be sure you limit this to your own source files; predefined and third-party headers are likely to make extensive use of predefined types.

But I wouldn’t make the prohibition absolute. There are a number of standard library functions that use predefined types. For example, in c = getchar() it makes no sense to declare c as anything other than int. And there’s no problem for something like for (int i = 0; i <= 100; i ++) ...

Ideally, the goal should be to use predefined types properly. The language has never guaranteed that an int can exceed 32767. (But “proper” use is difficult or impossible to verify automatically.)