D slower than C++ by a factor of _two_ for simple raytracer (gdc)

[bearophile]

Marius Muja Wrote:
> In my experience GDC code is faster than DMD code (in some cases significantly faster).

My experience is similar to the results you can see here, that is about the same on average, better for some things, worse for other ones:
http://shootout.alioth.debian.org/sandbox/benchmark.php?test=all&lang=gdc
(I was using GDC based on MinGW based on GCC 3.2. You can find a good newer MinGW here: http://nuwen.net/mingw.html but I don't know if it works with GDC).

Note for downs: have you tried -fprofile-generate/-fprofile-use flags for the C++ code? They improve the C++ raytracer speed some.

Bye,
bearophile