Size of Compiled Program

[Basile B. via Digitalmars-d-learn]

On Monday, 4 January 2016 at 13:49:03 UTC, Martin Tschierschke 
wrote:
> When I was writing a small speed test - D versus Ruby,
> calculating the first n prime numbers, I realized, that for 
> small n
> Ruby may be faster, than compiling and executing with D.
> But for n = 1,000,000 D outperforms Ruby by app. 10x.
>
> Looking at the size of my prime executable, it was around 800 
> kB with DMD
> and even with optimization and "gdc -Os" > 1 MB.
> Why is such a short program resulting in a so big binary?

You have the runtime and phobos compiled with your program. But 
also:
- if debug info are generated this increases the size.
- if bounds checking is turned off there is some code generated 
for each array operation
- if contracts are not off there is a lot of assertion that will 
be generated

see also some clues here:
http://forum.dlang.org/post/mailman.20.1441974998.22025.digitalmars-d-learn@puremagic.com