Re: [Mesa3d-dev] patch for some type alias bugs

[Brian P. <br...@va...>]

Josh Vanderhoof wrote:
> 
> Here's a patch that fixes some type alias bugs that show up with
> -fstrict-aliasing on gcc (which will be the default for gcc 3.0).  For
> the most part the patch just changes instances of
> 
>         *(xtype *)&y
> 
> which could possibly read from the address &y before the value of y
> has been written out to memory due to C aliasing rules, with
> 
>         ((union { xtype xt; ytype yt;} *)&y)->xt
> 
> which is safe for gcc since the created pointer can alias both xtype
> and ytype.  Hopefully other compilers will also assume union pointers
> can alias all of their member types.

I've applied the patch.  I put the typedef for fi_type in glheader.h
so it can be easily used anywhere.

-Brian