long compile time question

[Era Scarecrow]

On Wednesday, 24 October 2012 at 04:49:19 UTC, 1100110 wrote:
>> The following takes nearly three minutes to compile.
>> The culprit is the line bar ~= B();
>> What is wrong with this?

> I have the same issue on linux x64 2.060
>
> So appending to a dynamic array isn't really that efficient. 
> But this goes WAY over that line.  I'm timing your test now.
>
> It's still going...

  It appears it's all happening during copying init, why I am not 
sure.

[code]
struct B {
   enum SIZE = 1024 * 64;
   int[SIZE] x;
}

//same timing issue, no array involved
void test(B b) {}

void main() {
   test(B());
}
[/code]

  I've changed the *64 to various numbers and gotten curious 
results. The mb is the noted (estimated) memory footprint it used 
during compiling.

1:   0m0.725s   mb:??
2:   0m1.414s   mb:??
4:   0m2.620s   mb:28
8:   0m8.937s   mb:30
16:  0m35.869s  mb:34
32:  2m36.922s  mb:42
64:  9m27.353s  mb:56