waf: compiler flags, uninitalized variable

[Fred Wright]

On Fri, 1 Aug 2025, Hal Murray wrote:

> devel at ntpsec.org said:
>> Usually, you won't get that type of warning unless you enable it.  And
>> usually, you only get that type of warning in an optimized compile, since
>>  the dataflow analysis needed to detect it is part of the optimization
>> code.
>
> I tried O3.  That found a different maybe-uninitialized.
>
> I tried O6.  Nothing new.

The other thing I forgot to mention is that sometimes the control-flow 
analysis isn't as good in older compilers, leading to complaints about 
something being used uninitialized in a case where the code couldn't 
actually be reached in the unininitialized case.  Unless there's a good 
reason to avoid it, usually the best fix is just to add an initializer to 
the declaration, even if it's not logically necessary.

Fred Wright