Re: Add macros for diagnostic control, use them in locale/weightwc.h

[Paul Eggert <eggert at cs dot ucla dot edu>]

Joseph Myers wrote:
> it's established glibc practice not to add initializations that
> would change generated code to silence warnings.

Sure, and that's what the IF_LINT macro calls do in coreutils, Emacs, etc.: they 
don't alter the code used in production.  In practice this leads to code that is 
definitely easier to maintain and arguably more resistant against faults than 
the DIAG_IGNORE approach being proposed.

> that doesn't appear to help for the case this patch relates to; the
> uninitialized object '*((void *)&str+4)' is outside the bounds of "UCHAR
> str[1]"

If GCC is griping about (say) some component of the array xyz not being 
initialized, then in the worst case one can pacify it by initializing the array 
in its declaration, e.g., 'int xyz[100] IF_LINT (= {0});'.  Of course if GCC is 
griping only about xyz[2], one can tighten this by initializing just xyz[2], 
which is preferable.  In my experience, it's rare to need to do anything so 
drastic as to initialize an entire array, as GCC warning bugs generally have to 
do with local scalars.