Build portability: enable or disable warnings

[David Holmes]

Fredrik Öhrström said the following on 05/16/11 17:39:
> 2011-05-13 15:20, Andrew Haley skrev:
>> A recent patch (of mine, as it happens) broke builds on Debian and
>> Gentoo.  It was caused by a scanf call:
>>
>>          if (sscanf(chars, "%lx-%*lx", &x) == 1)
>>
>> which looks pretty innocuous, but it triggers a warning if -Wformat is
>> turned on:
> 
>> There are two ways to fix this: either force -Wformat and
>> -Wformat-security on when building HotSpot or force them off.  Either
>> would work, but my vote goes to the former.
> 
> I think it is better to fix the underlying complaint of the compiler.
> Thus change the sscanf string to "%lx-%*x"
> 
> The compiler is complaining that you over specify the second scanned
> parameter that is going to be thrown away anyway.

This particular issue has already been fixed.

I assumed Andrew was more generally questioning whether to force Wformat 
on or off rather than potentially have it vary depending on the compiler 
version.

David