Re: [Flex-devel] Direct yy_fatal_error instead of YY_FATAL_ERROR macro

[Aaron S. <aa...@se...>]

On Tue, 2008-12-02 at 10:36 -0500, Joe Krahn wrote:
> Aaron Stone wrote:
> > In the code generated for a reentrant scanner, two functions call
> > yy_fatal_error directly instead of going through the YY_FATAL_ERROR
> > macro. I believe this to be an omission. Any objections to changing it?
> ...
> 
> Actually, I had changed this in my mega-patch.

Oh cool, well then that makes two people who noticed this and made the
same change, so I'll see about committing it.

>
>  My modifications are 
> fairly extreme, so maybe it would be good if collected general bug-fixes 
>   to incorporate into the current code?

Ah, yes splitting things up is really good practice. Also, I had started
to review your patches but then lost the message list I had open. Lame
excuse, I know, but FYI that reading over your work is on my todo list.

> Another thing I fixed is the yywrap() macro. The yywrap function has 1 
> arg in the reentrant scanner, but zero otherwise. A blank argument is 
> valid for a macro, so yywrap(n) is actually valid code for an expression 
> using yywrap with either zero or one arguments.
> 
> It turns out that at least one broken compiler considers this an error, 
> claiming that a 1-argument macro was given zero args. There are also 
> non-broken compilers that give warnings. In my modified code, I switched 
> to using alternate definitions for yywrap, on the basis that it is 
> reasonable to emit warnings in this situation, even though it really is 
> valid code.

Interesting, I didn't know that!

Aaron