This isn't the right forum to discuss gcc bugs, but I don't want anyone
looking at my patch, wondering why there's this strange line in there,
thinking I'm insane.  Well, I mean, of course I *am* insane, just not
for that reason...   :-P


I made a discovery concerning the GNU C compiler - it has  a bug!   If
you look at the source code in my Colour Dispersion patch, you'll see a
line that goes

        strcat("A", 'a');

which accomplishes nothing, except that if it's removed and certain
compiler optimizations are turned on, POV-Ray will incorrectly render
refraction.  I hope to narrow POVRay down to a simple few-line test
program and pass it on to the GCC developers.  

The optimizations I used were:
   -O2 -mpentium -finline-functions

The problem goes away if (1) you change to -O1;  (2) your remove
-finline-functions; or (3) you insert an arbitrary call to a C library
function, such as printf or some string function, at a certain place in
the source code.

The gcc I use is version 2.8.1, compiled from source with pentium
optimizations.  I haven't even gotten as far as looking for the official
bug list for gcc.  


-- 

Daren Scot Wilson
Member, ACM
dar### [at] pipelinecom
www.newcolor.com
--
"A ship in a harbor is safe, but that is not what ships are built for"
                     -- William Shedd

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