On 6/22/24 01:35, William F Pokorny wrote:
> If the user posting in that issue was correct about g++13 turning on the 
> -fno-finite-math-only along with -ffast-math by default and it being the 
> cause of the problem, the safest thing to do is to configure with -fno- 
> fast-math (*) or use -fno-finite-math-only as suggested. (I cannot 
> reproduce the problem by turning finite-math-only on with my g++11.4 
> compiler...)

Update.

I upgraded from Ubuntu 22.04 to Ubuntu 24.04 over the weekend. The 
default g++ compiler is now 13.2.0 and builds do need to use the 
-fno-finite-math-only flag when using -ffast-math (*) with g++13 builds.

Rather than the camera issue, with yuqk, I see the 'bounding not working 
issue' issue reported in some fora here during the past year.

I expect given the different code bases, what will be seen as problems 
with g++13 builds will be varied. This includes introducing problems 
which might not be immediately apparent - the camera issues shows up 
more or less by chance for example, because of a test not really in play 
when it fails...

(I've not gotten around to re-building my collection of official releases.)

Bill P.

(*) - The default linux/unix builds with official releases use 
-ffast-math. The yuqk fork as shipped does not assume any compiler 
flags, but it does recommend -ffast-math with performance builds 
suggested in INSTALL.txt.  (**)

(**) - I've only lightly read up on the current g++13 --fast-math 
issues. However, it looks like gcc/g++ 13 plans to eventually back out 
the library changes creating the POV-Ray g++13 build exposures. 
Practically though, I think it best to always use -fno-finite-math-only 
when using -ffast-math with g++13 given we might not 'see' all the 
possible problems.

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