Re: RFC: -Wstrict-aliasing extension

[Mark Mitchell <mark at codesourcery dot com>]

Jim Wilson wrote:

> A customer moving from gcc-2.9x to gcc-3.x ran into problems with
> -fstrict-aliasing, and was disappointed that -Wstrict-aliasing did not
> help.
I'm not crazy about the false positive.  I have a strong bias against 
warnings with false positives, which I think comes from my background in 
error-checking tools.  So, I guess I'm disinclined towards this patch.  
But, not all that strongly.

I'm also disinclined towards adding more warning options, since I think 
it's already gotten very confusing for users.  Unless we're willing to 
go to the model where you have a list of error messages in a book, with 
numbers/names, so that people can look them up easily and turn on/off 
subsets of them.  I think right now we add lots of command-line options 
because that's easier than figuring out how to get warning groups that 
really work well for people, and then our cleverest users figure out how 
to get just what they want, but sometimes the less dedicated users 
compare us unfavorably to the competition.  On the other hand, since 
this is definitely our existing practice and the warning could be useful 
to some people, if you added it as a separate warning, I wouldn't object.

--
Mark Mitchell
CodeSourcery, LLC
(916) 791-8304
mark@codesourcery.com