How Do I Become Warning Free?

If you�re starting a new project from scratch, writing warningfree code is easy. But if you�re starting from an existing codebase, it can be much less straightforward. The chances are that the first time you increase your compiler�s warning level or run a new tool, you will disappear under a tidal wave of warnings. Often these result from systemic issues with the code�common mistakes you�ve made over and over again, which have gone unnoticed until now, but each instance of which generates a warning. There are also issues that tend to �percolate� through the code generating many warnings (const-correctness in C++ is a classic example).

The solution is to be pragmatic. Most static analysis tools provide fine-grained control over which warnings are generated where (via comments embedded in the source code, for example). Very often you can get the number down to a manageable level by switching off the one or two warnings that account for the majority or by excluding a �problem� module. You can go back and fix these other warnings at a later date, but you gain most of the benefit of static analysis in the interim.

The same approach can help on the rare occasions where a buggy tool generates spurious warnings for legitimate code, where you knowingly choose to write �questionable� code, or where a third-party library generates warnings.

Source of Information :  Paul Butcher - Debug it Find repair and prevent bugs