Sean Kelly wrote:
> bearophile Wrote:
>
>> C++ Static Analysis as done on the large Mozilla codebase:
>> http://blog.ezyang.com/2010/06/static-analysis-mozilla/
>> It shows that it's important to have a more powerful static reflection in D. It works well with scoped user-defined attributes too.
>
> As much as I like static analysis, it still has a long way to go. For example, here's some C code that a static analysis tool recently flagged as broken:
>
>     size_t fn( char** pdst, char* src, size_t srclen ) {
>         __thread static char* dst      = NULL;
>         __thread static size_t dstcap = 0;
>         if( dstcap < srclen ) {
>             dstcap = srclen;
>             dst      = realloc( dst, dstcap );
>         }
> memcpy( dst, src, srclen ); // Purify: ERROR - uninitialized write
>         *pdst = dst;
>         return srclen;
>     }
>
> Basically, it wasn't smart enough to realize that dst would
> always be non-NULL when the memcpy occurred, let alone that it
> would also always be large enough.  For such false positives,
> it's generally necessary to insert pointless code simply to
> silence the error, thus complicating the function and
> increasing the cost of maintenance.  I still believe that the
> benefits of static analysis vastly outweigh the cost, but I'd
> love to see more intelligence in branch analysis if nothing
> else.

realloc may return NULL. Perhaps they are catching that condition?

Ali

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