On Friday, 6 December 2013 at 22:20:19 UTC, Walter Bright wrote:
"there is no way proper C code can be slower than those
languages."
--
http://www.reddit.com/r/programming/comments/1s5ze3/benchmarking_d_vs_go_vs_erlang_vs_c_for_mqtt/cduwwoy
comes up now and then. I think it's incorrect, D has many
inherent advantages in generating code over C:
What surprises me most is claim that D can 'hypothetically'
generate more efficient code comparing with C, especially taking
into account current situation with code generation and
optimization.
The claim about inherent advantages implies that code generation
is not good now. If it can be so efficient, why it is not the
case? And if in practice it is worse, than who cares that 'in
theory' code can be better?
I believe that most of your points are either insignificant (like
array length - it is carried together with pointer almost
everywhere in C) or provide some marginal advantage. Such
advantages are offset by:
- huge runtime library
- constant runtime lib invocation and allocation stuff on heap
- horrible mangling (see
http://forum.dlang.org/thread/mailman.207.1369611513.13711.digitalmar...@puremagic.com
examples from hall of D mangling, mangling is so big, that forum
software goes astray)
- phobos snowball - one invocation of some function in standard
library leads to dozens template instantiations and invocations
of pretty much stuff
